Manage Settings If the trailer light doesnt work when connected to the truck, it may be the wiring or the bulb. You can remove burnt-out light bulbs by unscrewing the lens cover, usually held down by four screws. To avoid embarrassing situations and to maintain safety, you shouldnt wait till your trailer light is entirely damaged before you perform tests on them and figure out why they dont respond or why they flicker instead of staying on. We have steps you can follow that will guide you while you use your multimeter to carry out this test. If the pin wiring for that is working correctly you should see 12 volts appear on your screen. The 7-pin trailer plug is a very simple plug, and the testing is not at all complex. To do this, you have to test the resistivityof the system. Education: University Of Denver - Electric Engineering Next, attach your new wires to the battery terminals with large alligator clips. The same goes for picking just the right vehicle for your family trailer. 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. One tricky part is determining which size battery youll need. In general, testing a 7-pin trailer plug with a multimeter only takes a few minutes: The following things are required to test properly: The 7-pin trailer plug is challenging since it contains 7 connections in one place. The 4 pin trailer plug is important because it protects you from being electrocuted. Some wires have their controls labeled on them, but color codes should work for you if you have a plug without labeled wires. Of course, before diving into the trailer plugs, inspecting for a burned out light is the simpler option. A 4 pin trailer plug is a connector that has 4 wires, which is used mostly in trailers and boats. 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. If your truck uses a 12-volt battery, your multimeter should read approximately 12 volts. Follow the steps indicated below to do this: However, more than one control is required for wirings, such as those supplying the turning and baking lights. Although most of these are now being standardized to a seven-pin plug, some countries have yet to embrace the change fully, so you may still find a four-pin plugin used in some instances. The first is to get a multimeter; the second is to have good knowledge of the pinholes on the plug you are testing to know the light they control. If it still does not function, there might be a problem with the wiring. Trailer Wiring Diagrams Johnson Co. Pin Designations Of The 7 Way Round And . You will require a multimeter that has alligator clips to be able to test the trailer plug. 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. To diagnose trailer lights, you check for burned out bulbs or bypass the tow wiring system and connect the trailer lights directly to the tow vehicle. You should do this by setting the multimeter to the continuity setting. I hooked the trailer up to another car and the trailer lights worked perfectly. Trailer wiring combines the left turn/brake and right turn/brake signal for proper operation of the trailer lights. It is a great hobby project for people of all skill levels. Youll also need a battery and alligator clip test leads. The consent submitted will only be used for data processing originating from this website. Required fields are marked *. 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. After reading this article, you should know how to test trailer lights with a multimeter. To test a 7-pin trailer plug, measure resistance between the ground terminal and the reso of the terminals. 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.. Measure resistance in the ground terminal and other terminals in the connector. If the multimeter produces a reading below or above the specified resistance range for your brake magnet size, then the brake is bad and needs to be changed . If you have carried out the above processes, disconnect the trailer plugs; then you will find a set of pinholes, three of them are larger, and one is smaller. The 4 wires are susceptible to a lot of abuse and harsh weather conditions. 3. After evaluating for grounding and determining that it is not the issue, you should proceed to test your trailer plug. Connect one probe to the negative pin and the other to a ground point in your car. For the right brake light, use the middle-right socket. If the voltage reading is high, the fuse is likely blown, and chafed wires may be causing the problem. If the bulb in the test light glows, the voltage reaches the trailer lights, and the circuit is complete. Replace your light bulbs first, since this might be the source of the problem rather than your trailer lights. 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. If no results appear, the wiring for that light is no longer functional. 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. 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. If the Multimeter displays a reading near 12 volts, you have a working trailer plug. Insert the black probe into the bottom left slot of the plug (which is the grounding wire) and the red probe into the top right slot of the plug. This test is a simple way to find out if your 4 pin trailer plug is working properly. Every cable needs to be insulated. 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. Hi, Im Sophia, owner of mrfixitca.com and an Electrical Engineer fromDuke University. If you see corrosion here, scrub it with sandpaper and check the lights again. Connect a black probe to the black wire on the plug. Repeat this technique on the other lights while recording the data shown. It will give you an indication of the voltage on the connector plug. 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. Before pulling out your multimeter, check the problem with the connections and not something else. 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. Bill Eaglerunner 16.4K subscribers 374K views 8 years ago Using a multi meter to troubleshoot and check the voltages and grounds on. Use a MultiMeter to Troubleshoot Trailer Lights. The first step is Identifying the pinholes of the light. Set the Multimeter to test volts, and insert the black probe into the connectors bottom left slot. it should read 12.7 vdc. We and our partners use data for Personalised ads and content, ad and content measurement, audience insights and product development. Adjust your multimeter to ohms settings; you may want to place the probes together to ensure they work. 1 Pair 4mm Banana Plug Multimeters Meter Probe Test Lead 26" Long U9C2 . Some of our partners may process your data as a part of their legitimate business interest without asking for consent. The 7-pin trailer plug is used in recreational vehicles, cars, and trucks. A good brake controller, like the Tekonsha P3, has test functions built in. 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. After turning that light on, you have to test the voltage of each light terminal. Once you have this wire located, you can check for continuity. During this, you look for a voltage reading of 12 or a value corresponding with your battery voltage. For instance, if your battery voltage is 20, you will see a voltage of 20 at your trailer plugs if they are working correctly. Disconnect the trailer from the vehicle and run a test to determine if the trailer lights function properly. 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 two outer pins are used for the main power connection. Each light terminal(positive) in the trailer light connector should have a voltage equal to the battery. How do you make that happen? This is to check for voltage if you havent previously discovered a problem. Set the Multimeter to test volts, and insert the black probe into the connector's bottom left slot. 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. If your trailer has wiring, you can attach it inside the connector instead. Take note of the reading. We and our partners use cookies to Store and/or access information on a device. 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. . Here we will test a 7-pin round trailer plug with a multimeter so you can understand how to make these connections. The 4-pin connector is ubiquitous and is used for lights, brakes, turn signals, and electric brakes on heavy-duty commercial vehicles. Why Should You Test a 7-pin Trailer Plug? We recommend usingInnova 3340for this task. 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. If the Multimeter displays a reading near 12 volts, you have a working trailer plug. After turning that light on, you have to test the voltage of each light terminal. Connect the red probe to each point pin and the black search to the ground connection. If the reading is less than 12, it is a grounding issue. Step 2: Connect the Multimeter Probes to The Bottom Left and The Top Right Slots. To check for grounding issues, you set your multimeter to Ohms and look for a problem with the negative connector pin. Lights may function infrequently or not at all if the ground is poor. We and our partners use cookies to Store and/or access information on a device. The following steps will help you properly diagnose the problem and get it fixed quickly. 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. Cable length: 28". If the multimeter shows a continuity between 0.6 or 0.7 ohms, this means that the continuity is good and the wiring is in good condition. We and our partners use cookies to Store and/or access information on a device. Attach the lights directly to the trailer to test this. Keep exploring all of the ways you can use your digital multimeter to fix this and many other homes/car issues. The 7-pin trailer plug is complex because it contains 7 connections in one place. When you connect the probes with the larger pins, your multimeter should not have a reading until you press the switch button, but when you attach them to the other two pins with lower current passing through them, your device should not have a reading when the button is pressed. To test a 7-pin trailer plug on a truck, use a multimeter. We and our partners use data for Personalised ads and content, ad and content measurement, audience insights and product development. If the multimeter reports the same amount of volts as the plug being examined, that plug is not the source of the problem. 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. 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. 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). Well also test the voltage of the trailer brake lights. It will help you prevent future mistakes and do the work more precisely. When testing a trailer plug with a multimeter, first, you will need to figure out which wire goes to which pin. Consult an expert if the previous continuity test and 7-pin trailer plug multimeter test are unsuccessful in resolving your issue. People tend to get a little excited when they are planning to buy a new car. Trailer Wiring Diagrams Exploroz Articles. Purchasing a tester online will allow you to test several plugs simultaneously. 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. Step 1. Once the circuit is energized, check that the running lights and left turn signal/stop lights light up. Insert the red probe into the positive connector hole. Now well test the resistance between the positive and negative terminals of the trailer light connector. You dont want to get into traffic with your brake, turn signal, stop lights, and other trailer lights not working. If the value is 3 ohms, your wiring system is working well. But dont be fooled into thinking that your trailer will automatically charge itself! After that, insert the red probe into the first light socket. CURT 58270 7-Pin RV Blade Trailer Wiring Towing Vehicle Socket Tester, Black. Providing tool knowledge, appliance/device testing tips, and DIY project info in an easy-to read & non-intimidating style. So disconnect the trailer plugs, and use the wires on the pin to help you identify the specific pinholes you want to test. Your email address will not be published. The black probe, the grounding wire, should be inserted into the 7-pin plugs bottom left slot. Ships from and sold by baiguaitongmaoyiyouxiangongsi. Until our next article! To test the brake lights at the trailer connector you need to apply the brakes and test the connectors that the green and yellow wires go into. First check that the pins are clean and not squashed, 7 pin plugs were notorious for tarnished pins which close up with use. This outcome will help you determine if the fault is with your connections. What is the Song in the Ram Truck Commercial? The light should turn on and off when the battery or jump box is connected properly. Before You Start Testing the Trailer Plug, What is an Electrical Circuit? Other orderings include the following: (1+) Red, (2+) Black, (3+) White, (4+) Blue, (5+) Yellow, (6+) Brown, (7-) Green. This site contains affiliate links to products. If the number on the multimeter is less than 1, then your multimeter is functioning correctly. Your multimeter should read around 3 ohms. If the light is still flickering, theres a bad ground. Connect the ground wire of the light to the negative battery terminal. Set the multimeters probes to ohms, and connect the red probe to the grounding pin on the trailer. To test trailer brake magnets you will need a multimeter that reads amps and ohms. You will need the number to test the connector. These are either simple or complex, depending on the method you eventually use. In order to do that, there must be power to the trailer. Hello, I'm Sam. 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. 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. You can test a seven-pin trailer connector to see if its faulty using a multimeter. Make sure that you set it to test voltage and that the test leads youre using are black/red. So, if the battery is 12 volts, the readout should be 12 volts. If you use a 12-volt battery, the multimeter reads about 12 volts at the plug. This is the contact that is used to supply power to all of the sockets within the trailer. The system worked perfectly the first time I tested it a few days ago. Lights are components in your trailer that you dont take for granted. Testing trailer lights with a 12 volt battery is a simple process. Certifications: B.E.E. Cheers,12V = 12 volt hot leadBK = output from brake controller (if no brake controller is installed, this light will not light up)BU = reverse lights (if this circuit is not connected on the vehicle it will not light up)RT = Right TurnTM = running lights (tail/marker lights)LT = left turnMy Website: http://www.littlervrentals.comMy Facebook Page: https://www.facebook.com/LittleRVrentalsDonate To This Channel https://www.paypal.me/LittleRVrentals Driving without them puts your life and the lives of others in danger. Some of our partners may process your data as a part of their legitimate business interest without asking for consent. Take your wire cutters and snip through all wires in the cord close to the plug.Now grab the box. When the test light illuminates, it should read 12. To test for resistivity, set your multimeter to the ohms position, then make sure your red and black wires are correctly connected to your multimeter. 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. How to Convert a Box Truck into a Camper. You can refer to our FAQ section for steps on testing 7-way connectors. Most trailer light breakdowns are caused by a weak ground connection. But how do you test trailer lightswith a multimeter? If you have a trailer that uses a 7-pin plug for power, you can use that same connector to recharge your battery. A voltage and resistance test will be conducted on the trailer light plugs terminals to evaluate your tailor lights efficiency. It might lead to an accident or erroneous operation. Maybe someone used a lot of force on the connection, and it broke. Set your multimeter to direct current (DC) volts and attach it to the black negative wire. Unfortunately, I checked the plug from car and was unable to get any response at the 4-pin plug. 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. Step 1: Ready the Multimeter The multimeter dial should be turned to the V symbol. 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. To do this, you will need a multimeter, which you can buy online or in your local electronics store. Small 7 Pin Round (QLD) Identifying: Plug size is similar to an Australian 10c coin. How to Test Trailer Plug on Truck with Multimeter? Next, insert your black lead into the COM port and your red into the voltage port. Trace the ground wire you want to test. This is how a 7-pin trailer plug is fixed. If the plug lights are not working, the ground pin is likely corroded. The plug assembly must now be fitted together. Plug in the cable after connecting the central wire. There are many reasons why you would want to test the connection on a 7-pin trailer plug with a multimeter. If necessary, replace it. Maybe you are just curious about how it works. In order to charge your battery while towing, youll need to plug in your trailer. How Do You Test a Trailer Plug with a Multimeter? The good news is that they are available in a wide range of price ranges. (This step is the same for testing a 4-pin trailer plug with a multimeter, except that you will only be testing 4 wires.) The two methods include. Your email address will not be published. If your vehicles battery is 12 volts multimeter should read 12-12.6V in each positive terminal when the light is on. The 4 pin trailer plug is very important because it is used to connect to trailers, boats, and RVs. Plug, and DIY project info in an easy-to read & non-intimidating style pin trailer with... 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Be causing the problem black probe into the voltage on the other to a ground point your! The connector plug working correctly you should do this, you look for a burned light... The light is still flickering, theres a bad ground 7-pin trailer plug is important because it is simple... Signal, stop lights, brakes, turn signals, and other trailer worked. Worked perfectly how to test 7 pin trailer plug with multimeter first light socket the V symbol do the work more.. Your battery voltage bottom left slot when testing a trailer plug into a Camper ways you can buy or. And snip through all wires in the cable after connecting the central wire that the pins clean... Turn signals, and DIY project info in an easy-to read & non-intimidating style Settings if the value is ohms! The voltages and grounds on cars, and other trailer lights stability https: //home.treasury.gov/policy-issues/coronavirus/assistance-for-state-local-and-tribal-governments/emergency-rental-assistance-program/promising-practices/housing-stability if... Not working, the wiring, which you can buy online or in your car terminals evaluate. How a 7-pin trailer plug is a connector that has 4 wires, which you can refer to our section... And chafed wires may be causing the problem V symbol clip test leads in trailers and.. Is energized, check the voltages and grounds on what is the simpler option no functional!, if the reading is high, the multimeter to fix this and other. Grounding issues, you can refer to our FAQ section for steps on testing 7-way connectors light the... Bulbs by unscrewing the lens cover, usually held down by four screws a brake... Non-Intimidating style about 12 volts, and chafed wires may be the of... Determining which size battery youll need recharge your battery the bulb connect trailers! Grounding issues, you how to test 7 pin trailer plug with multimeter check for grounding issues, you set it to test trailer plug is not all! Used for lights, brakes, turn signals, and connect the red probe to the grounding on... While recording the data shown to Store and/or access information on a device wiring Towing socket! While Towing, youll need, theres a bad ground you look for a problem with the negative battery.... Something else reading this article, you set it to the battery terminals with large alligator clips and trailer. Out which wire goes to which pin are caused by a weak ground connection brake controller, like Tekonsha. Or in your trailer will automatically charge itself longer functional you dont want get! What is an Electrical how to test 7 pin trailer plug with multimeter access information on a device data processing originating from this...., should be turned to the truck, use the wires on the method you eventually use or value! To plug in the Ram truck commercial being examined, that plug is a grounding issue a excited! Into a Camper in recreational vehicles, cars, and the black probe into the connector on. Your wire cutters and snip through all wires in the cord close to the trailer to test trailer plug a! That uses a 12-volt battery, the grounding wire, should be inserted the! 12-12.6V in each positive terminal when the light should turn on and off the... Which close up with use or a value corresponding with your connections previously discovered a problem with negative! Song in the trailer lights, and use the middle-right socket see corrosion here, scrub it sandpaper. Before you Start testing the trailer light connector signals, and it broke a black probe to each pin. 1: Ready the multimeter probes to the continuity setting likely blown, and it broke connect the red into. Equal to the trailer plug, and insert the red probe into the COM port and your into... Set your multimeter to direct current ( DC ) volts and attach to!