You will require a multimeter that has alligator clips to be able to test the trailer plug. You dont want to get into traffic with your brake, turn signal, stop lights, and other trailer lights not working. To do so, first insert the probe into the ground pin and the other pins. Typically, there are four wires, each with a different color and a white grounding wire. If the new lights dont work, you move to the next diagnosis step. 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. The most important part of a 7-pin plug is the charging line. If you would like to change your settings or withdraw consent at any time, the link to do so is in our privacy policy accessible from our home page.. What Voltage Should a Diesel Truck Battery Be? A multimeter is a device we use to troubleshoot electrical systems and diagnose their faults sources. You should do this by setting the multimeter to the continuity setting. The plug assembly must now be fitted together. Connector type: banana plug, test pin. If you dont see any results, then the wiring for that light is no longer working. But dont be fooled into thinking that your trailer will automatically charge itself! If your vehicles battery is 12 volts multimeter should read 12-12.6V in each positive terminal when the light is on. Make sure youre not getting more than one volt. Youll need the following items in order to test it effectively: if(typeof ez_ad_units != 'undefined'){ez_ad_units.push([[250,250],'housetechlab_com-medrectangle-4','ezslot_4',121,'0','0'])};__ez_fad_position('div-gpt-ad-housetechlab_com-medrectangle-4-0');The 7-pin trailer plug is complicated because it hosts 7 different connections all in one (watch the video right below this paragraph). Use a MultiMeter to Troubleshoot Trailer Lights. You can remove burnt-out light bulbs by unscrewing the lens cover, usually held down by four screws. The black one would be for a negative connection, while the red one would be for a positive connection. Attach the lights directly to the trailer to test this. trailer 7 pin plug how to test - YouTube 0:00 / 1:59 trailer 7 pin plug how to test Guy Presse 2.55K subscribers 1.6K 605K views 11 years ago http://rv-mobile-services.ca/. For this you will need a multimeter that can read voltage in volts. During this, you look for a voltage reading of 12 or a value corresponding with your battery voltage. Rather than checking for multimeter readings, you see if the test light brightens up when you place the negative and positive probes at the appropriate connector pins and holes. This website uses cookies so that we can provide you with the best user experience possible. Connect the test light lead to the positive battery terminal and attach the metal end of the test light to the live wire of the trailer lights. 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. All you have to do is link up the white wire to the negative and the colored wires to the positive. Another way to diagnose a malfunctioning trailer is to remove the light bulb. They determine the safety of both you and other road users, which is a reason why laws that impose fines if these lights are bad exist. Check the fuse before replacing the screws and the back to prevent accidents. To do so, turn the multimeters ohm setting to 12 volts. Then attach the black probe to the negative terminal of the plug and the red probe to your grounding. Without a vehicle, testing trailer lights might not be as straightforward as connecting the red probe of your multimeter on each of the plug pins and the black on the negative connector to get a reading. Adjust your multimeter to ohms settings; you may want to place the probes together to ensure they work. It has both auto and manual ranging settings, its got a sturdy case, and has true RMS technology for accuracy. Before You Start Testing the Trailer Plug, What is an Electrical Circuit? You must know that most trailers have turning signals and brake lights connected to the same control cable. Connect the opposite wire to the positive terminal and switch on the light operated by that pin. To test yourground connection, you may take out your multimeter now and take out the two available probes. 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. Now apply the same process to the other control pinholes. So disconnect the trailer plugs, and use the wires on the pin to help you identify the specific pinholes you want to test. Youll be surprised how much power your trailer battery needs if its not charged. The top right slot of the plug should receive the red probe. The 7-pin trailer plug is a standard connector used on heavy duty trucks, trailers, and other large vehicles. The thrill of getting to pick out just the right vehicle for your family can be exhilarating. To do this, you will need a multimeter, which you can buy online or in your local electronics store. 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. 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. The white wire would be the ground wire and brown for the tail or running lights. Then connect the lights directly to your tow vehicle and test the running, brake, left, and right lights. If the multimeter reports the same amount of volts as the plug being examined, that plug is not the source of the problem. If your trailer plug is in order, your multimeter should have a reading approximately equal to the volts of your battery. 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! While the multimeter is the bread and butter of a typical electronics hobbyist, it is something that is often overlooked by people when trying to diagnose problems with their vehicles. In general, testing trailer lights with a multimeter can be done with a few easy steps. But they forget that the trailer needs a proper connection point, too one that will fit your vehicles wiring harness. If not, youve got a grounding problem, or youre not getting enough voltage. Lights are components in your trailer that you dont take for granted. If your truck uses a 12-volt battery, your multimeter should read approximately 12 volts. Testing for wiring problems might not be difficult, but the problem we face is how to begin; we have explained with detailed information how you can carry them out. 3. Then, your multimeter should provide a value close to the volts of your battery. Probe length: 19mm/0.7". This site contains affiliate links to products. Take a look at some of our related articles below. Fit the Batteries. 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. If this is correct, then your brake light switch is working correctly. Compare the multimeter reading with the ideal range. Trace the ground wire you want to test. How to Test Trailer Plug on Truck with Multimeter? Step 1. 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). To avoid problems, you should separate these wires by removing bulbs and checking each one separately. This video helps to paint a clearer picture. To troubleshoot the problems with your trailer lights, you must carry out an all-around test; you might need a multimeter and some cables for this diagnosis. Most of the faults with trailer lights are weak ground connections. If there is continuity, then the trailer is hooked up correctly. Take out your trailer connector, and place the black probe on the ground connection and the red probe on each point pin. If the multimeter reads less resistance than the ideal range, the circuit has been shorted, and resistance gets low. It will give you an indication of the voltage on the connector plug. We and our partners use cookies to Store and/or access information on a device. 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. To test the voltage, you need to remove the trailer plug and disconnect it. The 4 pin trailer plug is important because it protects you from being electrocuted. Refer to your vehicles owners manual for information on where to find these fuses. The 4-pin trailer plug is a fairly standard plug that is found on the back of an automobile. Wire the vehicle side wiring harness to a standalone battery. Plug in the cable after connecting the central wire. After turning that light on, you have to test the voltage of each light terminal. We and our partners use data for Personalised ads and content, ad and content measurement, audience insights and product development. Your email address will not be published. A trailer plug has seven wires, and if you are trying to figure out how to test a 7-pin trailer plug with a multimeter, you need to test each wire. 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. Remember, the black wire should go on the positive terminal and the white wire should be attached to the negative one. Your multimeter should read around 3 ohms. How to test a magneto coil with a multimeter? To do this, use the black wire to touch the green contact on the multimeter to the metal frame under the car lights. Bypassing the tow wiring system/trailer connector plugs. Now to test each of the lights to determine if any of the wirings for each light isnt working you will leave the black probe into the grounding slot of the plug. Amazon and the Amazon logo are trademarks of Amazon.com, Inc or its affiliates. Testing the 7-pin Trailer Plug is very important to ensure the safety of the towing vehicle and trailer. It will help you prevent future mistakes and do the work more precisely. I checked the 3 fuses related to the trailer; all looked fine. Disconnect the 7-pin plug from your vehicle. Measure resistance in the ground terminal and other terminals in the connector. Furthermore, keep in mind that these wires contain a sequence of connections. You want to check for voltage at the plug. It might lead to an accident or erroneous operation. You should also check the voltage of your trucks battery to ensure that your plug is connected properly. Is It Illegal to Ride in the Back of a Truck in Virginia? To test your trailer lights, you would need a multimeter. This site contains affiliate links to products. 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. A 4-pin connector is a very common type of connector that you will find on all sorts of equipment. Video | PIF DIY There are many reasons why you would want to test the connection on a 7-pin trailer plug with a multimeter. Then with your multimeter, perform a test on the ground connection, your trailer plugs, and finally on your lighting connector. Providing tool knowledge, appliance/device testing tips, and DIY project info in an easy-to read & non-intimidating style. Alternatively, you can use test bulbs to inspect your trailer lights and see if they are working. If you use a 12-volt battery, the multimeter reads about 12 volts at the plug. To test trailer brake magnets you will need a multimeter that reads amps and ohms. Continue with Recommended Cookies. If the Multimeter displays a reading near 12 volts, you have a working trailer plug. Most people who are involved in towing have to deal with 7-pin connectors which are used in towing. Make sure its configured to measure both DC and AC. 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. Insert the red probe into the positive connector hole. Ive been running my electrical warehouse in Sacramento for8 years. Hello, I'm Sam. One by one, measure the resistance between the ground terminal(negative) and all other terminals(positive). When tying a trailer to your truck, you should know how to test the seven pin plug wiring. Trailer wiring combines the left turn/brake and right turn/brake signal for proper operation of the trailer lights. 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. This is to check for voltage if you havent previously discovered a problem. If the Multimeter displays a reading near 12 volts, you have a working trailer plug. If the plug lights are not working, the ground pin is likely corroded. Set the Multimeter to test volts, and insert the black probe into the connector's bottom left slot. Cable length: 28". Flat connectors comply with Australian Standards AS4177.5-2004. Lights may function infrequently or not at all if the ground is poor. 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 Multimeter, or multimeter, is an instrument that measures multiple electrical quantities such as voltage, current, and resistance in electronic devices. The 7-pin trailer plug is used in recreational vehicles, cars, and trucks. It is to ensure that it is receiving the requisite voltage. $10.33. Trailer Wiring Connector Camping World. Then, check for continuity. Cut off the old plug and expose wires. Every cable needs to be insulated. To view the purposes they believe they have legitimate interest for, or to object to this data processing use the vendor list link below. Do the same to the other set of pins, and then press the switch. Education: University Of Denver - Electric Engineering Electrical engineering is my passion, and Ive been in the industry for over 20 years. We and our partners use cookies to Store and/or access information on a device. In the meantime, you can crimp an uninsulated butt connector to connect the exposed wires. The 7-pin truck test plug has a big brother in the form of the 7-pin round trailer plug. This plug is used to connect a bumper pull or fifth-wheel trailer to the vehicle. If the lights dont work, you have a clue that the problem may be from the wires. With a multimeter, you can test different things like power, voltage, resistance, and continuity. Certifications: B.E.E. 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. This will complete the circuit and allow you to test for continuity. 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. One of the easiest methods involves using a multimeter. These can be the result of blown fuses or chafed wires. To test the continuity setting's calibration, touch the 2 terminals together and hold them in place. There are a lot of different types of 4 pin connectors so what do you do when you need to test one? One of the most important accessories for any auto enthusiast is a multimeter. We recommend usingInnova 3340for this task. Just a random guy who likes to build things. How Do You Diagnose Trailer Wiring Problems? 3) Have a helper work the brakes while you touch the sharp end of the test light to one of the pins. The best part is that you can usually DIY solve the problem because these techniquespinpoint the problem for you. If the trailer light doesnt work when connected to the truck, it may be the wiring or the bulb. References(1) color codes https://www.computerhope.com/htmcolor.htm(2) wiring system https://www.youtube.com/watch?v=ulL9VBjETpk. The 4 pin trailer plug is unique in the sense that it is designed to carry heavy loads. To fix a replacement bulb, place the bulb on the socket and turn it anticlockwise until it clicks. To test 4 pin trailer plug, measure resistance between the ground terminal and a ground point in your vehicle. The approach to fixing your trailer light would depend on the faults you have diagnosed. The trailer plug is important because it has a system of electrical wiring that protects you from getting electrocuted. These are the same connections that you tested for the turn signals. Replace your light bulbs first, since this might be the source of the problem rather than your trailer lights. 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. After reading this article, you should know how to test trailer lights with a multimeter. 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. Hopefully, this post is enough to understand how to test your trailer lights. I will teach you how to test your 7-pin trailer plug with a multimeter in this guide. Trailer Wiring Diagrams Exploroz Articles. If it continues to show this after repeated testing, it implies that the trailer plugs are in good operating order. We may receive a commission for purchases made through these links. 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. Four of them are used for lights, and the other three are used for electric brakes. After that, insert the red probe into the first light socket. The white wire is used to connect a 4 pin plug to a 7 pin plug. then its time to take it to a professional, Multimeter with black/red probes that can test forvolts, 2 people one to run the vehicle and one to run the multimeter. The full ISO standard is ISO 1446 for 13 pin connections. Whatever the case, testing the connections on a 7-pin trailer plug with a multimeter is very easy. The most common 7-pin trailer plug pinout has the following order: (1+) Black, (2+) Red, (3+) Yellow, (4+) Blue, (5+) White, (6+) Brown, (7-) Green. The same goes for picking just the right vehicle for your family trailer. The system worked perfectly the first time I tested it a few days ago. 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. . The real color of the item may be slightly different from the pictures shown on website caused by many factors such as brightness of your monitor and light brightness. The first step in testing the wiring is to use a multimeter. For example, connect your red probe to the control for the left signal, then turn on your left signal light. (Image from Varta). If your trailer has wiring, you can attach it inside the connector instead. Once you confirm that these are working, you move to your trailer plugs. Next, check the ground pin of the plug against the positive pins. There are many great multimeters on the market, but I have my own personal favorites which are perfect for automotive uses: Innova 3340:This Innova multimeter is one of those all-around good multimeters but specifically its great for automotive uses as it can test both volts and amps, plus temperatures, continuity, and much more. Education: University Of Denver - Electric Engineering If you want to test trailer brakes out of your vehicle, you will need a battery and a test light. Touch the metal parts of your terminals together to make sure it works. If the light is still flickering, theres a bad ground. How To Test 7 Pin Trailer Plug With Multimeter Housetechlab. Place your black multimeter probe on this negative pin and test for issues by grounding the positive probe connection on a metal surface. Then you would find out the lighting system is connected through three significant pinholes for the positive connectors, but there is an extra small opening for the negative connector. The plug is characterized by three pinholes for the positive connectors and a tiny opening for the negative connector. Check your vehicle's plug configuration. 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.