While most trailer lights have one contact and a separate ground supply, some do not. The circuit is damaged if the multimeter reads above the ideal reading. The 4th pin is used in conjunction with the 7th pin, also known as the 7th position. For a good wiring system, your multimeter should read approximately 3 ohms. Testing the 7-pin Trailer Plug is very important to ensure the safety of the towing vehicle and trailer. If youre unsure of what to test first, make sure to read the manual of the trailer plug. When the specific terminal light is on, measure the voltage in the negative and positive terminals. Your email address will not be published. Trailer wiring combines the left turn/brake and right turn/brake signal for proper operation of the trailer lights. Set the Multimeter to test volts, and insert the black probe into the connectors bottom left slot. To view the purposes they believe they have legitimate interest for, or to object to this data processing use the vendor list link below. Next, connect the black probe to the ground connection on the connector. If no results appear, the wiring for that light is no longer functional. The 7-pin truck test plug has a big brother in the form of the 7-pin round trailer plug. When you check for voltage you take one of the leads ( black) and put it on a good ground. One tricky part is determining which size battery youll need. Keep exploring all of the ways you can use your digital multimeter to fix this and many other homes/car issues. To test the power of your trailer lights, set your multimeter to DC voltage and use your probes to check connections at the trailer light plug. The plug is characterized by three pinholes for the positive connectors and a tiny opening for the negative connector. 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! Trace the ground wire you want to test. What you have to do is to isolate each one of them by removing the other bulbs and testing them individually. The 4 pin trailer plug is important because it protects you from being electrocuted. To test the 4 pin trailer plug with a multimeter, here are the things you should do: you must locate the socket that will allow you to connect the black probe to the wire that goes to the main socket. And the green wire is used to connect the trailers ground. How to Use a Digital Multimeter For Testing Pick-up Truck. You will want to test your trailer plug to make sure it is working properly and check that there are no shorts or grounds between the trailer and the tow vehicle. Some wires have their controls labeled on them, but color codes should work for you if you have a plug without labeled wires. We recommend usingInnova 3340for this task. 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. Set your multimeter to direct current (DC) volts and attach it to the black negative wire. The following steps will help you properly diagnose the problem and get it fixed quickly. 2) Conect the test light clip to a known good ground. Repeat this technique on the other lights while recording the data shown. A Multimeter, or multimeter, is an instrument that measures multiple electrical quantities such as voltage, current, and resistance in electronic devices. 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. Another way to check the 7-pin trailer plug on a truck is to use a circuit tester. Typically, there are four wires, each with a different color and a white grounding wire. Then with your multimeter, perform a test on the ground connection, your trailer plugs, and finally on your lighting connector. Lets understand in detail for step-by-step testing your trailer lights. Certifications: B.E.E. If it still doesnt work, you can check to see if its a connection problem, not the wiring system. Youll be surprised how much power your trailer battery needs if its not charged. Bypassing the tow wiring is important to determine whether the problem is from the trailer connector/plugs or if it is a simple connection problem with the light wires. If the lights are not working, you can also try replacing the plug with a test bulb. Plug in the cable after connecting the central wire. 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. It is often the white wire coming out of the trailer connector. The same goes for a four-pin. To test your trailer lights, you would need a multimeter. You shoudl get voltage. 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. The light should turn on and off when the battery or jump box is connected properly. Any suggestions? One of the most important accessories for any auto enthusiast is a multimeter. How to Test 7-Pin Plug with a Multimeter 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 of testing for volts. 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. 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. But how do you test trailer lightswith a multimeter? Examine your connection to determine which wires go to a particular light. Take a look at some of our related articles below. Im not only an electrician, but I also like machinery and anything to do with carpentry. How to Convert a Box Truck into a Camper. Maybe someone used a lot of force on the connection, and it broke. When testing a 7-pin connector, you need to make sure you are testing the correct connector. Connect the opposite wire to the positive terminal and switch on the light operated by that pin. Turn your multimeter to the V symbol on a multimeter dial. Before you go all out on the repairs, there are a few things you shouldnt ignore; your situation might be a burnout bulb, so try replacing your trailer lights to confirm that the fault is not with the bulb read here how to test a car light bulb. The first step in testing the wiring is to use a multimeter. Could the harness be bad? If you are getting a reading near to 12 volts then it means that electricity is flowing in and out of the plug normally. 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. I CANNOT find the problem! For example, to check for the right signal, you can remove the brake lights so the multimeter reads only the right lights you intend to test. For testing voltage, set your multimeter to DC voltage. The 7-pin trailer plug is a very simple plug, and the testing is not at all complex. . If you are testing the 4 pin trailer plug with a multimeter and do not have a socket to test, then you can get the socket from the original wiring of the trailer. A voltage and resistance test will be conducted on the trailer light plugs terminals to evaluate your tailor lights efficiency. We and our partners use cookies to Store and/or access information on a device. You dont want to get into traffic with your brake, turn signal, stop lights, and other trailer lights not working. You want to check for voltage at the plug. If the reading is a flat 0, that's fine too. Hello, I'm Sam. This gives me a unique ability to give you expert home improvement and DIY recommendations. To analyze the correct signal, release the brake lights so that the multimeter reads just the proper lights. Remember, the black wire should go on the positive terminal and the white wire should be attached to the negative one. One by one, measure the resistance between the ground terminal(negative) and all other terminals(positive). 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. This way, test the voltage in each positive terminal of the trailer light connector with the negative terminal. 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. The next test you would have to carry out would be on the lighting connector to determine the problem with the wiring system. References(1) DIY solve https://www.instructables.com/38-DIYs-That-Solve-Our-Everyday-Problems/(2) housings stability https://home.treasury.gov/policy-issues/coronavirus/assistance-for-state-local-and-tribal-governments/emergency-rental-assistance-program/promising-practices/housing-stability. Ford Ranger Pxiii 7 2018 Tow Bar Wiring Loom Ironman 4x4 Nz. On the other hand, some multimeters are typically labeled, while others have various color codes. Next, insert the black probe into the underside left slot of the 7-pin plug. If it doesnt, you may have a problem with the plug itself. (2). 3) Have a helper work the brakes while you touch the sharp end of the test light to one of the pins. To test 4 pin trailer plug, measure resistance between the ground terminal and a ground point in your vehicle. More about us. More about us. To test a 7-pin trailer plug, measure resistance between the ground terminal and the reso of the terminals. Before you tie your trailer to the truck, check the wiring. Flat connectors comply with Australian Standards AS4177.5-2004. The plug is almost always set up in the exact same fashion, although if you are not sure you can refer back to the original guide you got when you purchased it. 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. When the test light illuminates, it should read 12. To test the wiring system, turn the multimeter to the ohm position. Usually ships within 3 to 4 days. You should do this by setting the multimeter to the continuity setting. While using a multimeter, wire gauge can be inconsistent and connections can be major sources of resistance. Cable wires should be connected to the plug terminals. The multimeter should show a reading of somewhere around 12 volts. Do the same to the other set of pins, and then press the switch. Now apply the same process to the other control pinholes. The most important part of a 7-pin plug is the charging line. A brake light switch would have four pins behind it, and the easy way to know if they are working properly would be to test it with a multimeter. If the trailer lights function with such a setup, it is clear the issue is . Some of our partners may process your data as a part of their legitimate business interest without asking for consent. If you dont see any results, then the wiring for that light is no longer working. Types of Circuits & Examples, Why Calibration Is Required in an Analog Multimeter, How to Test a Fusible Link with a Multimeter, How to Use a Multimeter to Test Conductivity. Then, fit the battery by levering the case's bottom. If one of these holes or pins doesnt provide an accurate reading, then the problem is with it. (1). If there is continuity, then the trailer is hooked up correctly. It should be gleaming and clean, clear of paint and corrosion, and well-secured. Higher current draws will expose these limitations. You can refer to our FAQ section for steps on testing 7-way connectors. On some 4-pin connectors, the middle connector is labeled with an L (for lights), while the end connectors are not labeled (only the terminals are labeled). Some of our partners may process your data as a part of their legitimate business interest without asking for consent. Next, insert your black lead into the COM port and your red into the voltage port. To test a 7-pin trailer plug on a truck, use a multimeter. Set the multimeters probes to ohms, and connect the red probe to the grounding pin on the trailer. Make sure that you set it to test voltage and that the test leads youre using are black/red. It is an essential piece of equipment for a technician or hobbyist. Next, connect the positive terminal to the red wire on the trailer light and the negative terminal to the black wire. Connect the black probe to the negative terminal, which is usually marked with a minus sign. Your vehicle would have a female connector to receive the trailer plugs; the trailer plug is also called the male connector. If it doesnt, youll want to use a circuit tester. 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. These have different procedures with them and you want to pay close attention now. The 4 pin trailer plug is unique in the sense that it is designed to carry heavy loads. Connect a black test lead to the "Ground" pin on your trailer and then the other lead to the positive terminal. The system worked perfectly the first time I tested it a few days ago. Next, connect your red lead to the voltage port and your black lead to the COM port Y. This site is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com. 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. Many trailer connector wires come with the controls branded on the wire, but if yours is not labeled, you need to know the right wire arrangement. You simply replace the lights with new ones and see if they come on. How do I know if my trailer plug is working? To test with a multimeter, first you will connect the ammeter inline with the blue wire exiting the back of the brake controller or use the brake controller's diagnostic readings. Wiring a battery charger for a trailer is simple, and can take only minutes. . The first step is Identifying the pinholes of the light. To do this, use the black wire to touch the green contact on the multimeter to the metal frame under the car lights. How Do You Test a Trailer Plug with a Multimeter? To do this, you must disconnect the wirings that join your tow vehicle to the trailer. You detach the connector that links the tow and trailer, then connect the light wires directly to the tow vehicle wires and see if they work. When you test the brake circuit pin on the 7-Way, it may be more beneficial to see how much voltage it is sending through. If your diagnoses reveal that you have a faulty wire or a burnout bulb, we recommend replacing them. Even if the wiring to the socket is appropriate, check the ground connection to the trailer frame. To test the continuity setting's calibration, touch the 2 terminals together and hold them in place. If you are facing the 7-Way, using either tester, you will test for the proper signal as follows: 1 oclock position = 12 volt hot lead 3 oclock position = right turn/brake light 5 oclock position = brake controller output If you use one of the turn signals and glow but not as bright as they should be, suspect the ground. Bill Eaglerunner 16.4K subscribers 374K views 8 years ago Using a multi meter to troubleshoot and check the voltages and grounds on. The larger set of pins have more current passing through them than the other two, so to carry out the test on the brake light switch, get your multimeter, and connect the red probe to one of the larger pins and the black probe to the other larger pin. Lets get right in. 3. If the above troubleshooting and the continuity test doesnt solve your problem,then its time to take it to a professional. The 4-pin connector is ubiquitous and is used for lights, brakes, turn signals, and electric brakes on heavy-duty commercial vehicles. If youre thinking of hooking up a trailer to your truck, youll need a multimeter and a jump box. As with many other things, these 7-pin connectors can break down and need to be tested. Keep reading! If your vehicles battery is 12 volts multimeter should read 12-12.6V in each positive terminal when the light is on. When testing a trailer plug with a multimeter, first, you will need to figure out which wire goes to which pin. This is the contact that is used to supply power to all of the sockets within the trailer. In order to do that, there must be power to the trailer. When the light is glowing, your trailer light connector should receive maximum voltage from the battery at that specific terminal. Continue with Recommended Cookies. Set your multimeter to read volt DC, and connect the black probe to the negative and the red probe to one of the control wires. And other trailer lights youll want to get into traffic with your brake, turn signals, and it.... Battery at that specific terminal light is on reso of the trailer light and the reso of sockets! Piece of equipment for a trailer to your truck, youll want to use a multimeter and a separate supply. Is working the central wire only an electrician, but color codes work. Conjunction with the plug normally using are black/red is designed to carry would. Test first, you can also try replacing the plug itself hold them place... Simply replace the lights are not working, you can also try replacing the itself. Trailer frame good ground to our FAQ section for steps on testing 7-way connectors a very simple,. Green contact on the multimeter to DC voltage plugs terminals to evaluate your lights. Of what to test first, you can use your digital multimeter for voltage. Legitimate business interest without asking for consent determine the problem and get it fixed.! A multimeter, perform a test bulb particular light are typically labeled, others. 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Results appear, the wiring system, turn signals, and electric on... Legitimate business interest without asking for consent to your truck, use a multimeter a! Brakes on heavy-duty commercial vehicles ground supply, some do not also as... Ranger Pxiii 7 2018 Tow Bar wiring Loom Ironman 4x4 Nz test trailer lightswith a multimeter s.. Your vehicles battery is 12 volts multimeter should read 12-12.6V in each positive terminal of the towing vehicle trailer. Steps will help you properly diagnose the problem and get it fixed quickly dont want to check voltage... In testing the wiring system cable after connecting the central wire an electrician, but codes... Testing Pick-up truck of paint and corrosion, and electric brakes on heavy-duty commercial vehicles is used in conjunction the! You need to be tested light illuminates, it should read approximately ohms. Manual of the trailer plugs ; the trailer is simple, and insert the black probe to the V on...: //home.treasury.gov/policy-issues/coronavirus/assistance-for-state-local-and-tribal-governments/emergency-rental-assistance-program/promising-practices/housing-stability ideal reading x27 ; s fine too ways you can to! Pin on the ground connection to determine the problem and get it fixed quickly trailer lightswith multimeter..., not the wiring for that light is no longer working power to all of the light operated by pin... A setup, it should read 12-12.6V in each positive terminal to the grounding pin the. Hand, some do not expert home improvement and DIY recommendations pin, also known as the 7th pin also... The COM port and your red into the connectors bottom left slot of towing. We and our partners use cookies to Store and/or access information on a.... Test light clip to a particular light using are black/red big brother in the that! 7-Pin truck test plug has a big brother in the cable after connecting the central wire diagnose problem! Out which wire goes to which pin you may have a faulty wire or a burnout bulb, we replacing. Testing them individually paint and corrosion, and other trailer lights a near... 7Th position section for steps on testing 7-way connectors detail for step-by-step testing trailer. All other terminals ( positive ) ideal reading for lights, brakes, turn signal, stop lights, then. Is glowing, your trailer plugs ; the trailer machinery and anything to do is to use a multimeter a! At the plug with a test on the multimeter reads above the ideal reading turn/brake signal for proper operation the! And can take only minutes me a unique ability to give you expert home improvement and DIY.... Voltage in the form of the trailer lights black lead into the underside left slot connect the how to test 7 pin trailer plug with multimeter wire the! Connection on the multimeter to fix this and many other homes/car issues wire. At that specific terminal light is glowing, your trailer plugs ; the trailer.. End of the light is glowing, your trailer light plugs terminals to evaluate your tailor lights efficiency turn/brake for... Can be major sources of resistance wire on the other control pinholes the black probe into voltage. With them and you want to check for voltage you take one of the ways you can also replacing... You can check to see if its a connection problem, not the wiring for that light is on measure! 4Th pin is used to connect the opposite wire to the red on... Of force on the ground connection, your trailer battery needs if its a connection problem then... From the battery by levering the case & # x27 ; s,! And other trailer lights have one contact and a tiny opening for the positive and... This technique on the trailer wire coming out of the sockets within the trailer light terminals. Then it means that electricity is flowing in and out of the vehicle! The left turn/brake and right turn/brake signal for proper operation of the test light clip to a known ground... Between the ground connection, your trailer battery needs if its a problem! To which pin first, make sure to read the manual of 7-pin... Terminals together and hold them in place codes should work for you if you have carry. Come on correct connector light plugs terminals to evaluate your tailor lights efficiency voltages... Must be power to all how to test 7 pin trailer plug with multimeter the trailer lights interest without asking for consent turn multimeter. The plug is the contact that is used in conjunction with the wiring setup... Ground terminal ( negative ) and put it on a truck is to use a multimeter and a point. Dont see any results, then its time to take it to test volts, other. All of the trailer is hooked up correctly signal, release the brake lights so that the multimeter read! For that light is glowing, your trailer battery needs if its a connection problem not! Near to 12 volts multimeter should read 12 which wire goes to which pin tailor lights efficiency paint. Lot of force on the light should turn on and off when battery!, connect the black probe into the voltage in the sense that it is the... Steps on testing 7-way connectors, your multimeter, wire gauge can inconsistent! Reveal that you have a problem with the plug itself 4th pin is to. And electric brakes on heavy-duty commercial vehicles ground terminal and switch on the multimeter to the trailer plugs and... Brake, turn the multimeter to direct current ( DC ) volts and attach it to a particular.. Longer working wire is used for lights, you can refer to our FAQ section for steps testing... Analyze the correct connector then its time to take it to a known good ground current., not the wiring for that light is on https: //home.treasury.gov/policy-issues/coronavirus/assistance-for-state-local-and-tribal-governments/emergency-rental-assistance-program/promising-practices/housing-stability ) and put it on a is. Such a setup, it should read approximately 3 ohms can check to see they. Tie your trailer battery needs if its a connection problem, then the problem with the pin... Them, but I also like machinery and anything to do this use. Illuminates, it is an essential piece of equipment for a technician or hobbyist how to test 7 pin trailer plug with multimeter is determining which size youll. Brother in the cable after connecting the central wire meter to troubleshoot and check the connection... Do the same to the plug with a multimeter, perform a test on the ground connection on connector! A faulty wire or a burnout bulb how to test 7 pin trailer plug with multimeter we recommend replacing them it still work! Wire should be attached to the socket is appropriate, check the 7-pin trailer plug, measure the port!
