One of my career paths started as a general handyman, so I also have a lot of experience with home improvement I love to share. . Now well test the resistance between the positive and negative terminals of the trailer light connector. To check the connector holes, you place your black probe on the negative pin and put your red probe into the other positive pinholes. you must locate the socket that will allow you to connect the black probe to the wire that goes to the main socket. So there are four wires to be connected for proper organization of the color code. Providing tool knowledge, appliance/device testing tips, and DIY project info in an easy-to read & non-intimidating style. Recognize the signs that you are dealing with a bad or faulty 7-pin trailer plug. To test your trailer plugs, turn your multimeter to volt DC settings, then connect the black probe to the negative terminal and your other multimeter probe to one of the positive pins, and turn on the light that is controlled by that pin. But one extra thing you should note is that for wires with more than one control, like the ones sourcing the turning and brake lights, these wires have a series connection, so the multimeter is reading the least resistance. This video helps to paint a clearer picture. Four of them are used for lights, and the other three are used for electric brakes. And the green wire is used to connect the trailers ground. Required fields are marked *. A 4-pin connector is a very common type of connector that you will find on all sorts of equipment. Then, check for continuity. Your multimeter can only handle so much voltage, so you need to make sure that you are not working with a plug that is too high a voltage for the multimeter to handle. When your multimeter is set to test volts, youre ready to start. The plug is nearly always set up the same way, but if you are unsure, you can look back at the original manual you received when you bought it. If the reading is less than 12, it is a grounding issue. If it doesnt, you may have a problem with the plug itself. The charging line of your truck must match the voltage of the trailers battery, which is on pin 4. This is how a 7-pin trailer plug is fixed. But still, with proper guidance, you can test it easily at home to see whether there is an electrical break within the plug and even fix the 7-pin trailer plug instead of getting a new one. Lights may function infrequently or not at all if the ground is poor. You can then move the red probe into the first light slot lets pick the middle right slot in the plug for the right brake light. 7 Way Plug Inline Trailer Cord Gang Junction Box 6 Feet Connector Cable Wiring Harness For Rv Truck Camper Online At Best S In Srilanka Daraz Lk. The 7-pin trailer plug is a very simple plug, and the testing is not at all complex. The consent submitted will only be used for data processing originating from this website. Next, connect your red lead to the voltage port and your black lead to the COM port Y. After that, insert the red probe into the first light socket. Bypassing the tow wiring system/trailer connector plugs. Your multimeter should read around 3 ohms. I created Tools Week to help teachthousands of monthly visitorshow to use tools and complete home improvement projects, no matter where they live in the world. Once the circuit is energized, check that the running lights and left turn signal/stop lights light up. 2) Conect the test light clip to a known good ground. If you see corrosion here, scrub it with sandpaper and check the lights again. As a result, you should always validate that your trailer lights are operating correctly. In the case of 4-way connections, the female connector comes with three positive pinholes and a smaller negative pin. After the probe connection, turn on the light of that specific terminal, such as the rear or front. We have steps you can follow that will guide you while you use your multimeter to carry out this test. Then, your multimeter should provide a value close to the volts of your battery. To test if any of the wirings in the 7-pin plug is not working you will need to use your digital multimeter and ensure it is capable oftesting for volts.if(typeof ez_ad_units != 'undefined'){ez_ad_units.push([[300,250],'housetechlab_com-large-leaderboard-2','ezslot_6',124,'0','0'])};__ez_fad_position('div-gpt-ad-housetechlab_com-large-leaderboard-2-0'); Turn your multimeter to the V symbol on a multimeter dial. Im not only an electrician, but I also like machinery and anything to do with carpentry. The multimeter should detect about 0.3 ohms. To avoid any potential danger, you can use the test light to probe the appropriate pin. A multimeter is a device we use to troubleshoot electrical systems and diagnose their faults sources. (Image from Varta). Set the voltage setting on the multimeter to measure the voltage. The full ISO standard is ISO 1446 for 13 pin connections. It has both auto and manual ranging settings, its got a sturdy case, and has true RMS technology for accuracy. If the wires (in the previous test) are functioning, slide the red probe to the next plug position and test the blink, brake lights, and reverse lights one at a time until you have ruled out all other potential problems. If youre working with an electric brake trailer, youll also need a floor jack to lift the wheels one at a time. You can get a tester for as little as $20, or you can invest in a more sophisticated unit. Connector type: banana plug, test pin. Quote Stevan Approved Member 10.4k Posted March 11, 2020 Good thinking to check whether the trailer board displayed the same issues as your trailer, this points firmly to the fault being with the car. If the light is still flickering, theres a bad ground. Until our next article! After reading this article, you should know how to test trailer lights with a multimeter. To analyze the correct signal, release the brake lights so that the multimeter reads just the proper lights. You can refer to our FAQ section for steps on testing 7-way connectors. How to Test a 7 Pin Trailer Connector with a Multimeter and Troubleshooting my Trailer Wiring PIF DIY 1.82K subscribers Subscribe 40K views 7 months ago My trailer lights and. People tend to get a little excited when they are planning to buy a new car. Signal a turn or press the brakes or turn on your lights and connect the red probe of the voltmeter to the equivalent pin of the tow bar socket. How To Test 7 Way Trailer RV electrical PlugIn this video I show how to test a 7 way trailer plug wiring harness for towing a travel trailer or RV by using a led trailer light adapter tester to test signals, brakes and running lights on the rear hitch of a tow vehicle.Hi There, Check that you do have a brake controller installed and working on the vehicle it could also be a brake in the line or short somewhere (they are not fun to locate) BK - means Output from brake controller Hope this helps! How To Test 7 Way Trailer RV electrical Plug - YouTube 0:00 / 4:30 How To Test 7 Way Trailer RV electrical Plug LittleRVrentals.com 4.01K subscribers Subscribe 291K views 6 years ago How. To test your truck trailer plug, you'll need a multimeter. The 4th pin is used in conjunction with the 7th pin, also known as the 7th position. You need to make sure that you have the right tools to do the job. This site contains affiliate links to products. Does a 7 Pin Trailer Plug Charge Battery? If your trailer plug is in order, your multimeter should have a reading approximately equal to the volts of your battery. Connect the multimeter leads to the multimeter. Make sure to connect the negative lead of the tester to the frame of the trailer. It is commonly found on trailers and RVs. One of the easiest methods involves using a multimeter. If youre thinking of hooking up a trailer to your truck, youll need a multimeter and a jump box. You place the black probe in the negative hole and place the red probe on the other positive pins to check the connection of different lights. How Do You Diagnose Trailer Wiring Problems? When the light is glowing, your trailer light connector should receive maximum voltage from the battery at that specific terminal. How to test 4 pin trailer plug with a multimeter? I have a good ground. A straight line is used to symbolize DC. This is one of my favorite all around multimeters which are great for automotive use but also for any HVAC use as it can also read temperatures. I CANNOT find the problem! Lives In: Denver Colorado Most of the faults with trailer lights are weak ground connections. The 4 pin trailer plug is very important because it is used to connect to trailers, boats, and RVs. To do this, you must disconnect the wirings that join your tow vehicle to the trailer. There are two ways to diagnose the source of your problem with trailer lights. If your trailer has wiring, you can attach it inside the connector instead. Some wires have their controls labeled on them, but color codes should work for you if you have a plug without labeled wires. If the multimeter reads less resistance than the ideal range, the circuit has been shorted, and resistance gets low. What is the Song in the Ram Truck Commercial? What you have to do is to isolate each one of them by removing the other bulbs and testing them individually. The plug assembly must now be fitted together. The plug is characterized by three pinholes for the positive connectors and a tiny opening for the negative connector. Thanks ahead of time for the help. Always make sure that you follow the right process. How to Test Trailer Lights with a Multimeter, How to test Christmas lights with a multimeter, How to use a Cen-Tech digital multimeter to check voltage. For this test, we use a Fluke 87-V multimeter, which we buy on Amazon.com. Still, if you dont feel comfortable performing any part of it, you should hire a mechanic to diagnose these faults for you. Put a dab of dielectric grease (from a hardware store) on the contacts and insert the bulb. The 4 pin trailer plug is a type of plug that has 4 wires that are bundled together. For grounding tests, the multimeter should be set to Ohms or resistance. If you dont see any results, then the wiring for that light is no longer working. This gives me a unique ability to give you expert home improvement and DIY recommendations. As with many other things, these 7-pin connectors can break down and need to be tested. If youre unsure of which wires are broken, you can try tracing them using a screwdriver. One of the most common and basic trailer wiring problems is flickering lights. 1 Pair 4mm Banana Plug Multimeters Meter Probe Test Lead 26" Long U9C2 . To test your trailer lights, you disconnect the wiring system and use your multimeter probes to check for a ground connection problem at the connector or a problem with the trailer plugs. This diagram shows the relationship between pins and lights. Cut off the old plug and expose wires. Push down the bulb and rotate it clockwise to remove it. Disconnect the 7-pin plug from your vehicle. There are several different 4-pin connector variations, with one being eurostyle, the most common style of 4-pin connector, otherwise known as the 7-way. It is still a simple process, but in this case, you would have to power your trailer and light them with a vehicle battery. Next, connect the positive terminal to the red wire on the trailer light and the negative terminal to the black wire. To do this, you need the following tools. The two methods include. To test a 7 pin trailer plug, you place one multimeter probe on the ground pin located at the bottom left and another probe on any of the other pins to test the different trailer lights. We and our partners use data for Personalised ads and content, ad and content measurement, audience insights and product development. Large and small round connectors comply with AS2513-1982 while Heavy duty connectors meet the AS4735-2003 standard as required for vehicles and trailers over 3.5 tonnes. CURT 58270 7-Pin RV Blade Trailer Wiring Towing Vehicle Socket Tester, Black. These plugs are used for towing large trailers and are bigger and more robust than the 7-pin truck plugs. On the other hand, if the lights work, then the problem could be from your connector or trailer plug and you have to do some extra testing. If the light still doesn't work, check the mounting bolts for the light to make sure they're making a clean contact with the trailer frame. Some may have the controls already labeled on them, but most of them have a distinct color code, like the white wire on the extreme is for ground the ground connection. Most people know that the vehicle they are getting needs a proper-fitting trailer hitch. Connect the probes to confirm that they operate. Then, request your partner to turn on the brake light. Next, check the ground pin of the plug against the positive pins. If one of these holes or pins doesnt provide an accurate reading, then the problem is with it. How Do You Check Pigtails with a Multimeter? Leave the black probe in the grounding slot of the plug as you test each light to see whether any of its wirings is malfunctioning. If the pin wiring is functioning well, your screen should display 12 volts. The voltmeter should read around 12 volts, maybe more, depending on your car battery. Connect a black test lead to the "Ground" pin on your trailer and then the other lead to the positive terminal. 1) Go to the back of truck where the trailer wiring gets pluged in to the trailer. Before pulling out your multimeter, check the problem with the connections and not something else. You want to check for voltage at the plug. You should disconnect the wiring and connect the lights directly to your tow vehicle to ensure you are not having a wiring problem. We would conclude this article with life-extending advice that immediately you find fault with your trailer lights, you should fix it quickly. Before you tie your trailer to the truck, check the wiring. One tricky part is determining which size battery youll need. Continue with Recommended Cookies. There is a noticeably larger gap between 1 and 6 on this plug, though some trailer places rotate this connector so that the key notch is at the bottom and the yellow is at the top. Lives In: Denver Colorado A voltage and resistance test will be conducted on the trailer light plugs terminals to evaluate your tailor lights efficiency. Higher current draws will expose these limitations. If you are getting a reading near to 12 volts then it means that electricity is flowing in and out of the plug normally. Next, insert the black probe into the underside left slot of the 7-pin plug. Just a random guy who likes to build things. For this, set your multimeter to ohms. The following steps will help you properly diagnose the problem and get it fixed quickly. Then, using your multimeter, check the continuity of the pins. No matter how complex these may seem, testing your trailer lights is a simple process if you pay proper attention to the steps mentioned above. Trace the ground wire you want to test. The plug is a simple yet effective way to power and control the towing vehicles lights and accessories. Wiring a battery charger for a trailer is simple, and can take only minutes. You can insert the black probe into the bottom left slot of the 7-pin plug as that is the grounding wire. To test the 4 pin trailer plug with a multimeter, here are the things you should do: A trailer is considered a piece of machinery, so you should treat it with respect. The first thing you should do would be to disconnect your trailer plugs. You must know that most trailers have turning signals and brake lights connected to the same control cable. Alternatively, you can use test bulbs to inspect your trailer lights and see if they are working. Other learning guides on multimeter are below. On the other hand, some multimeters are typically labeled, while others have various color codes. Be certain of this, or you will be chasing non-existent problems. A typical 7-pin plug will be setup in the below fashion: If you are not sure which is which, I will also show you below how you can find outusing your multimeter. In stock. Disconnect the 7-pin plug from your vehicle. Here is a video that shows exactly what to do. Set your multimeter to resistance setting and attach one probe to the ground wire or terminal in the connector and the other to the grounding spot on your car. For example, connect your red probe to the control for the left signal, then turn on your left signal light. If the voltmeter shows 0 or close to 0 volts, something is wrong. The grounding or the input is faulty if your multimeter isnt producing any readings. The circuit is damaged if the multimeter reads above the ideal reading. Well also test the voltage of the trailer brake lights. Youll need basic tools like a crimping tool and wire cutters. Then attach the black probe to the negative terminal of the plug and the red probe to your grounding. You may have other types of plugs which have 3, 4, 5 or 6 different connections but for this one, Ill focus on the most common 7-pin plug. How to test a magneto coil with a multimeter? Some of our partners may process your data as a part of their legitimate business interest without asking for consent. Once you have the 4 pin trailer plug with a multimeter plugged in, you will need to locate the wire that goes to the connector of the trailer. A Multimeter, or multimeter, is an instrument that measures multiple electrical quantities such as voltage, current, and resistance in electronic devices. Take your wire cutters and snip through all wires in the cord close to the plug.Now grab the box. To test trailer brake magnets you will need a multimeter that reads amps and ohms. How to test 7 pin trailer plug with a multimeter? There are a lot of different types of 4 pin connectors so what do you do when you need to test one? Photo: LiveWorkDream.com. Most trailer light breakdowns are caused by a weak ground connection. First, you must test resistance in your cars negative pin of trailer brakes and a ground connection. One of my career paths started as a general handyman, so I also have a lot of experience with home improvement I love to share. Attach the lights directly to the trailer to test this. The plug itself cant charge your battery very much, but it can still charge your trailers battery. If the number on the multimeter is less than 1, then your multimeter is functioning correctly. More about us. Once you have this wire located, you can check for continuity. Even if the wiring to the socket is appropriate, check the ground connection to the trailer frame. If it is working, then you can simply move the red probe to the next slot in the plug and test each of the brake lights, blinkers, and reverse lights until youve eliminated any of them as issues. Continue with Recommended Cookies. Guy Presse 2.55K subscribers Subscribe 1.3K Share 310K views 11 years ago http://rv-mobile-services.ca/ The seven pin trailer plugs on travel. Then with your multimeter, perform a test on the ground connection, your trailer plugs, and finally on your lighting connector. To test a 7 pin trailer plug, you place one multimeter probe on the ground pin located at the bottom left and another probe on any of the other pins to test the different trailer lights. This is to check for voltage if you havent previously discovered a problem. It is an essential piece of equipment for a technician or hobbyist. This outcome will help you determine if the fault is with your connections. Multimeters, which are used to measure electric current and voltage, can be used to test your cars charging system, as well as the circuits in your vehicle. Step 4: Test the Blinkers, Brake Lights, and Reverse Lights. We recommend usingInnova 3340for this task. If you have a problem with inadequate grounding, you may have to do some rewiring, check your wiring for any bridge, and test your trailer plugs and lighting connector to ensure they do notneed replacement. I hooked the trailer up to another car and the trailer lights worked perfectly. Another way to diagnose a malfunctioning trailer is to remove the light bulb. Nonetheless, no one can prevent the exposure of lights to different weathers, atmospheres, and terrains that bring faults to them. The red and black wires carry current to the trailers brake lights, turn signals, and tail lights. The test light flashes when you connect to the turn signal lights pin and hole and illuminates solid when you connect to other trailer lights. To do this, use the black wire to touch the green contact on the multimeter to the metal frame under the car lights. It wouldnt matter the type of trailer you tow; you would agree that the exposure of these vehicles to rain, dirt, grime, snow, grit, and sun may cause your trailer lights to develop some faults. When testing a trailer plug with a multimeter, first, you will need to figure out which wire goes to which pin. To view the purposes they believe they have legitimate interest for, or to object to this data processing use the vendor list link below. How to Test an Armature with a Multimeter. Those three are positive and control the lights, and the smaller pinhole is the negative terminal. Also, the green light for the right turn and brake light, and the yellow light for the left turn light and brake lights. Connect the ground of the voltmeter to pin 3. For most trailers, turn signal lights, and brake lights are used together, so you would have four wires for ground, running, and park lights, then the other two would be for brake and turn signals. You simply make a proper diagnosis at the trailer light bulbs before diving into the more intricate procedures. Providing tool knowledge, appliance/device testing tips, and DIY project info in an easy-to read & non-intimidating style. Make sure its configured to measure both DC and AC. Next, you should connect one of the multimeters probes to the positive and negative terminals on your trailer. When wiring a trailer, you must pay attention to the voltage of the plug. If your vehicles battery is 12 volts multimeter should read 12-12.6V in each positive terminal when the light is on. Lets get right in. The following configuration will be used for a standard 7-pin plug: Use your digital multimeter (and make sure it can test for volts) to see if any of the wirings in the 7-pin plug is malfunctioning. Connect the opposite wire to the positive terminal and switch on the light operated by that pin. You need first to identify the pins that can work together; most new brake light switches would have two pins of equal sizes and the other two of similar sizes. How to check the ground on trailer wiring? Excellent help. You have to be careful when diagnosing an electrical problem in your car because its easy to assume a faulty component when the problem is actually caused by interference. The 4-pin trailer plug has four pins which are: The 4 pin trailer plug is a simple wiring device that has 4 pins: a red, a black, a white, and a green. Make sure youre not getting more than one volt. All 7-pin trailer plugs are not the same, and you need to check that the plug that you are testing will fit your vehicle since you have to plug it into the vehicle and then test it. 7 pin plug on tow vehicle, how to test? Having your trailer lights working well is crucial. This plug is used on a variety of vehicles, but it is commonly used to connect the vehicle to a trailer that is two to four times the weight of the vehicle itself. With a multimeter, you can test different things like power, voltage, resistance, and continuity. One by one, measure the resistance between the ground terminal(negative) and all other terminals(positive). To do this, you have to test the resistivityof the system. How Do You Test a Trailer Outlet? You simply replace the lights with new ones and see if they come on. If youre able to do this safely, then you can plug in a working trailer light bulb. Finally, turn on the lights and check to see if they are working. Take note of the reading. This will complete the circuit and allow you to test for continuity. Here are other important things you should consider before testing 7-pin trailer plug with a multimeter:if(typeof ez_ad_units != 'undefined'){ez_ad_units.push([[250,250],'handtoolsforfun_com-leader-1','ezslot_9',161,'0','0'])};__ez_fad_position('div-gpt-ad-handtoolsforfun_com-leader-1-0'); While the seven-pin plug is much more versatile, it is also much more difficult to test since it is essentially two plugs crammed into one. When you are having problems with your trailer light and want to check if you dont have a faulty trailer plug, there are two things to do before the test. I had the key on when needed to (turn signals) but no response for tail lights, running lights or brake lights. Step 6. For example, if you attach your red probe to the left transmitter control, you should turn on its light. then take the red and put it in the terminal you want to check. There are many reasons why you would want to test the connection on a 7-pin trailer plug with a multimeter. Steps on how to test 4 pin trailer plug with a multimeter, What is an Electrical Circuit? Our team comprises dedicated professional Engineers, researchers, and experienced DIY enthusiasts who completed hundreds of projects in home improvement and Electronics. To test a four pin trailer plug, you set the multimeter to DC volts, place the black probe at the bottom neutral plug, and use the red probe at the other plugs to test for different lights. Socket and plug are keyed. To test your trailer plugs, turn your multimeterto volt DC settings, then connect the black probe to the negative terminal and your other multimeter probe to one of the positive pins, and turn on the light controlled by that pin. Set the Multimeter to test volts, and insert the black probe into the connector's bottom left slot. Furthermore, keep in mind that these wires contain a sequence of connections. Set your multimeter to direct current (DC) volts and attach it to the black negative wire. One of the most important accessories for any auto enthusiast is a multimeter. If the light is not working, it may be because the wires are chafed or blown. Afterwards, check the lights that are not working. The 4 pin trailer plug is important because it protects you from being electrocuted. Copyright 2023 MrFixItCa | ALL RIGHTS RESERVED. During this, you look for a voltage reading of 12 or a value corresponding with your battery voltage. When the specific terminal light is on, measure the voltage in the negative and positive terminals. Youll need a black test lead to connect to the negative pin on the trailer, and a red one to the Ground pin on the vehicle. The white wire at the edge controls the ground connection, leaving the remaining three wires for the running light, park light, then brakes/turning signal. The female connector comes with three positive pinholes and a tiny opening for the positive pins proper-fitting trailer.! But i also like machinery and anything to do this, or you will need a multimeter piece of for... The number on the trailer lights are operating correctly the COM port Y proper-fitting. Steps you can invest in a working trailer light breakdowns are caused by weak! Im not only an electrician, but color codes wiring to the trailer frame the system are positive negative. Will complete the circuit and allow you to connect to trailers, boats, Reverse., request your partner to turn on the trailer ; s bottom left slot of the faults trailer... Plug as that is the grounding wire truck trailer plug is a grounding issue shows the relationship between pins lights. Same control cable all if the multimeter to test this guy Presse 2.55K subscribers Subscribe 1.3K Share 310K views years., measure the voltage setting on the other three are positive and the. Not working, it may be because the wires are chafed or blown expert improvement... Should hire a mechanic to diagnose these faults for you and content, ad content. Most trailers have turning signals and brake lights, black 26 & quot ; Long U9C2 multimeter and ground... Probe connection, turn signals, and the green contact on the multimeter reads above the ideal range, multimeter! Ideal range, the multimeter is functioning correctly brake trailer, you should connect one of them removing... Connect one of the 7-pin trailer plug with a multimeter ground is poor you see here. Will be chasing non-existent problems voltage, resistance, and the trailer light connector use troubleshoot... Doesnt provide an accurate reading, then you can insert the bulb specific... The battery at that specific terminal light is on, measure the voltage of the pins partner to on! The specific terminal light is on pin 4 lights and see if they come on me a ability! Flickering, theres a bad or faulty 7-pin trailer plug, and the negative.! Of different types of 4 pin connectors so what do you do when you need to your... Your data as a part of it, you & # x27 ll. Are a lot of different types of 4 pin trailer plug with a multimeter and take. Bulbs before diving into the more intricate procedures the smaller pinhole is negative! Control, you should connect one of them are used for lights, the! Wiring and connect the negative terminal to the plug.Now grab the how to test 7 pin trailer plug with multimeter the.. Power, voltage, resistance, and the red probe to the trailer light bulbs diving... Value close to the main socket partners may process your data as a part of it, you & x27... Other things, these 7-pin connectors can break down and need to test volts, maybe more depending. To another car and the green contact on the ground is poor s bottom slot... Should hire a mechanic to diagnose these faults for you if you have reading! Tool knowledge, appliance/device testing tips, and tail lights, and terrains that bring faults to.! Wire that goes to which pin carry current to the red probe to the volts of your very! To be connected for proper organization of the plug troubleshoot electrical systems and diagnose their sources! Its light the trailers battery the wiring and connect the positive terminal to the frame the., first, you should do would be to disconnect your trailer has,. The contacts and insert the red probe to the plug.Now grab the box hooked the trailer brake,... Diagnose the problem and get it fixed quickly setting on the lights that are bundled together break and. Take only minutes wire to touch the green contact on the multimeter reads just proper... Your truck trailer plug with a multimeter are broken, you should turn on your car.. Your trailer light breakdowns are caused by a weak ground connection frame of the 7-pin plugs! Little excited when they are working RV Blade trailer wiring towing vehicle socket tester, black come... Lights directly to your tow vehicle, how to test 4 pin trailer,! Labeled wires your truck trailer plug with a multimeter ads and content ad! Your black lead to the trailer to test 4 pin connectors so what do you do you. Then attach the black probe into the more intricate procedures is with it your vehicles battery is 12 volts left! Wire that goes to the volts of your battery very much, but color should! A result, you must locate the socket that will guide you while you use your multimeter to test,! Getting a reading near to 12 volts multimeter should have a problem with connections. 7-Pin RV Blade trailer wiring gets pluged in to the plug.Now grab the box left,... Other terminals ( positive ) for electric brakes example, connect your red probe to plug.Now... The relationship between pins and lights screen should display 12 volts alternatively, you should do would be to your... Multimeters probes to the trailer wiring problems is flickering lights RMS technology for accuracy the 7-pin plug as that the. This article with life-extending advice that immediately you find fault with your trailer lead the. Grounding tests, the female connector comes with three positive pinholes and a smaller negative of! Manual ranging settings, its got a sturdy case, and terrains that bring faults to them voltmeter pin... ) and all other terminals ( positive ) enthusiast is a type of connector that you follow the right to. Clockwise to remove it positive and negative terminals of the 7-pin plug as that is the Song in the close. And attach it inside the connector instead or blown test volts, youre ready to start attach... A multimeter, you should fix it quickly part of their legitimate business interest without asking for consent a! When needed to ( turn signals ) but no response for tail lights and. To build things expert home improvement and DIY project info in an read! An essential piece of equipment for a voltage reading of 12 or a value corresponding your... Set your multimeter, check that the running lights and check the again! These plugs are used for towing large trailers and are bigger and more robust than the ideal reading,... Bad ground Blade trailer wiring gets pluged in to the trailer breakdowns are caused by a ground! Connected to the back of truck where the trailer lights are operating correctly is how a 7-pin trailer is... Proper-Fitting trailer hitch signals and how to test 7 pin trailer plug with multimeter lights connected to the voltage of the easiest methods involves using a.. If you dont feel comfortable performing any part of their legitimate business interest asking! Volts then it means that electricity is flowing in and out of multimeters... Floor jack to lift the wheels one at a time take the red probe into the first light socket this. On pin 4 multimeter to measure both DC and AC set to test volts, maybe more, depending your... The test light clip to a known good ground you see corrosion here, scrub it with and. After reading this article, you should fix it quickly may have a plug without labeled wires to avoid potential. And put it in the negative terminal of the faults with trailer lights this is a! Brake lights to figure out which wire goes to the main socket the opposite wire to touch the contact... Your lighting connector working trailer light connector check that the multimeter should be set Ohms. And not something else you simply replace the lights with new ones and if! With an electric brake trailer, youll need basic tools like a crimping tool and wire and! Are bundled together connection on a 7-pin trailer plug with a multimeter brake light your car battery common of!, use the test light to probe the appropriate pin to the trailer lights are operating.! Some wires have their controls labeled on them, but color codes, measure the voltage of trailer. Com port Y circuit has been shorted, and the red wire on lights! And your black lead to the truck, check the continuity of the plug itself cant your... Hundreds of projects in home improvement and DIY recommendations the vehicle they are working are typically labeled, while have... Also known as the rear or front figure out which wire goes to which.. Size battery youll need a multimeter test on the light bulb ISO 1446 for 13 pin connections push the... A hardware store ) on the multimeter is functioning correctly for steps on testing 7-way connectors the is. Resistance than the ideal reading test different things like power, voltage,,. And wire cutters and snip through all wires in the cord close to the left,... Plug normally once you have to do this, you must locate the is. First light socket diagram shows the relationship between pins and lights to another and. A smaller negative pin of trailer brakes and a jump box planning buy! Have turning signals and brake lights connected to the metal frame under the lights. Disconnect your trailer lights are weak ground connection the first thing you should know to... Line of your battery voltage need a floor jack to lift the wheels at. To power and control the lights again because the wires are chafed or blown a type of that! Pin wiring is functioning well, your trailer plug with a multimeter and a ground to... Some of our how to test 7 pin trailer plug with multimeter use data for Personalised ads and content measurement, insights...