Typically, there are four wires, each with a different color and a white grounding wire. If the value is 3 ohms, your wiring system is working well. If youre able to do this safely, then you can plug in a working trailer light bulb. If this is correct, then your brake light switch is working correctly. Connect the probes to confirm that they operate. Consult an expert if the previous continuity test and 7-pin trailer plug multimeter test are unsuccessful in resolving your issue. If there is continuity, then the trailer is hooked up correctly. If the light is not working, it may be because the wires are chafed or blown. Electrical engineering is my passion, and Ive been in the industry for over 20 years. If you dont see any results, then the wiring for that light is no longer working. Trailer Wiring Diagram Plugs Sockets. There are many reasons why you would want to test the connection on a 7-pin trailer plug with a multimeter. Your multimeter should indicate the value corresponding to the voltage of the battery you are using. 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 multimeter should read 0-.3 ohm resistance. Socket and plug are keyed. As a result, youll never have to worry about the cause of trailer lights malfunctioning. 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. 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. When the specific terminal light is on, measure the voltage in the negative and positive terminals. How Do You Diagnose Trailer Wiring Problems? Do trailer harnesses have fuses? It would be a wrong choice to be in traffic without running lights, brake lights, and left and right lights. The 4 pin trailer plug is a type of plug that has 4 wires that are bundled together. Take note of the reading. Take out your trailer connector, and place the black probe on the ground connection and the red probe on each point pin. You will need the number to test the connector. It will help you prevent future mistakes and do the work more precisely. The same goes for a four-pin. You look for a reading of 0.3 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. For instance, if your battery voltage is 20, you will see a voltage of 20 at your trailer plugs if they are working correctly. The first step in testing the wiring is to use a multimeter. These plugs are used for towing large trailers and are bigger and more robust than the 7-pin truck plugs. 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.. Why Should You Test a 7-pin Trailer Plug? Then, fit the battery by levering the case's bottom. The most critical aspect of connecting trailer lights is wiring the system up, and for the lights to function rightly, you should get the proper cables. Step 6. In general, testing trailer lights with a multimeter can be done with a few easy steps. If you have confirmed the fault is not an inadequate grounding, next you have to test the trailer plug to be sure if it is receiving voltage. 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. These are the same connections that you tested for the turn signals. The multimeter dial should be turned to the V symbol. Every cable needs to be insulated. You can get a tester for as little as $20, or you can invest in a more sophisticated unit. Lets understand in detail for step-by-step testing your trailer lights. These have different procedures with them and you want to pay close attention now. Other plug types with 3, 4, 5, or 6 different connections may be available, but Ill concentrate on the most typical 7-pin plug for this article. 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. And the green wire is used to connect the trailers ground. If you use one of the turn signals and glow but not as bright as they should be, suspect the ground. 7 Blade To 6 Round. Next, insert your black lead into the COM port and your red into the voltage port. You can test the voltage of these lights using a multimeter. References(1) color codes https://www.computerhope.com/htmcolor.htm(2) wiring system https://www.youtube.com/watch?v=ulL9VBjETpk. To avoid problems, you should separate these wires by removing bulbs and checking each one separately. Bypassing the tow wiring system/trailer connector plugs. If this is correct, the faults are not with your trailer plugs. The trailer plug is important because it has a system of electrical wiring that protects you from getting electrocuted. To view the purposes they believe they have legitimate interest for, or to object to this data processing use the vendor list link below. Trailer Byrnes Krickl. 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 7-pin truck test plug has a big brother in the form of the 7-pin round trailer plug. It is often the white wire coming out of the trailer connector. If the trailer lights function with such a setup, it is clear the issue is . Cut off the old plug and expose wires. Most of the faults with trailer lights are weak ground connections. It might lead to an accident or erroneous operation. If you get a constant reading, then the trailer plugs are functioning correctly. Make sure its configured to measure both DC and AC. You dont want to get into traffic with your brake, turn signal, stop lights, and other trailer lights not working. It is still a simple process, but in this case, you would have to power your trailer and light them with a vehicle battery. When the test light illuminates, it should read 12. I hooked the trailer up to another car and the trailer lights worked perfectly. Measure resistance between ground terminals(negative) and all positive terminals. The light should turn on and off when the battery or jump box is connected properly. Do the same to the other set of pins, and then press the switch. 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. We and our partners use data for Personalised ads and content, ad and content measurement, audience insights and product development. If your multimeter is showing no results, it means either the grounding or the input isnt working. Hopefully, this post is enough to understand how to test your trailer lights. 1 Pair 4mm Banana Plug Multimeters Meter Probe Test Lead 26" Long U9C2 . If the reading is a flat 0, that's fine too. If your trailer has wiring, you can attach it inside the connector instead. Then connect the other probe to the positive terminal on the jump box or battery to see if the trailer is powered. Hi, Im Sophia, owner of mrfixitca.com and an Electrical Engineer fromDuke University. If youre working with an electric brake trailer, youll also need a floor jack to lift the wheels one at a time. A 4 pin trailer plug is a connector that has 4 wires, which is used mostly in trailers and boats. 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. 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. They are used to connect a trailer to the towing vehicles wiring system. 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. Then attach the black probe to the negative terminal of the plug and the red probe to your grounding. 3. Well also test the voltage of the trailer brake lights. First, you must test resistance in your cars negative pin of trailer brakes and a ground connection. Still, if you dont feel comfortable performing any part of it, you should hire a mechanic to diagnose these faults for you. Set the Multimeter to test volts, and insert the black probe into the connector's bottom left slot. Please Tell Us How We Can Improve This Article. $10.33. There are two ways to diagnose the source of your problem with trailer lights. To test the ground pin, insert the black probe into the negative hole and the red probe into the positive pins. Education: University Of Denver - Electric Engineering If youre unsure of which wires are broken, you can try tracing them using a screwdriver. Always make sure that you follow the right process. 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. Your multimeter may report the reading value with the low resistance. Remove the cables that connect the primary car to the trailer. You must measure resistance to evaluate the lighting connection. You must know that most trailers have turning signals and brake lights connected to the same control cable. During this, you look for a voltage reading of 12 or a value corresponding with your battery voltage. It is commonly found on trailers and RVs. It is to ensure that it is receiving the requisite voltage. If the voltage reading is high, the fuse is likely blown, and chafed wires may be causing the problem. (Image from Varta). You can insert the black probe into the bottom left slot of the 7-pin plug as that is the grounding wire. How to Check Truck Trailer Plug with Multimeter? The 7-pin trailer plug is a standard connector used on heavy duty trucks, trailers, and other large vehicles. To do this, you have to test the resistivityof the system. Required fields are marked *. 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. Trailer Wiring Diagrams Exploroz Articles. Touch the metal parts of your terminals together to make sure it works. Check your vehicle's plug configuration. For the lap mas830b multimeter, you would use a 9V battery. If the reading is less than 12, it is a grounding issue. Each light terminal(positive) in the trailer light connector should have a voltage equal to the battery. But dont be fooled into thinking that your trailer will automatically charge itself! Just a random guy who likes to build things. 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. You can remove burnt-out light bulbs by unscrewing the lens cover, usually held down by four screws. A good idea is to consult the owners manual to locate the fuse and the wires. A 7-pin plug (sometimes referred to as the "7-way trailer connector") is the connector and heavy-duty wire that brings the necessary power and related functions to the trailer you're towing. 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 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. We and our partners use cookies to Store and/or access information on a device. You must wear gloves as security and then measure resistance and voltage in your trailer lights connector terminals, as mentioned in the guide above. Even if the wiring to the socket is appropriate, check the ground connection to the trailer frame. If not, check the converter box. Well also test the voltage of the trailer brake lights. Step 1 - Do the necessary check on your trailer lighting Step 2 - Test for grounding Step 3 - Examine your trailer plugs Conclusion Testing your trailer lights For you to fix your trailer lights, a multimeter is an essential equipment since this tool helps you troubleshoot the electrical systems as well as detecting the source of break down. If you dont want to have any problems, you have to make sure that you do everything that you need to do in order to test a 7-pin trailer plug with a multimeter. Trace the ground wire you want to test. This site contains affiliate links to products. Next, connect the positive terminal to the red wire on the trailer light and the negative terminal to the black wire. 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. What is the Song in the Ram Truck Commercial? We and our partners use data for Personalised ads and content, ad and content measurement, audience insights and product development. You should make sure it is set to DC volt settings. How Do You Test A 7 Pin Trailer Plug With A Multimeter? Im not only an electrician, but I also like machinery and anything to do with carpentry. 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. If the connection is weak, then crimp it to ensure a secure connection. Check the back of the 7-pin plug to find out which wire goes to which pin. Next, connect your red lead to the voltage port and your black lead to the COM port Y. If you want to test trailer brakes out of your vehicle, you will need a battery and a test light. Your email address will not be published. You simply make a proper diagnosis at the trailer light bulbs before diving into the more intricate procedures. As truck drivers, we strongly feel you are not strangers to handling machinery or sorting out an electrical system. To test yourground connection, you may take out your multimeter now and take out the two available probes. In the meantime, you can crimp an uninsulated butt connector to connect the exposed wires. If the above troubleshooting and the continuity test doesnt solve your problem,then its time to take it to a professional. Next, check the ground pin of the plug against the positive pins. As a professional handyman, I often test 7-pin trailer plugs with a digital multimeter without any trouble. 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 To Test 7 Pin Trailer Plug With Multimeter Housetechlab. Put a dab of dielectric grease (from a hardware store) on the contacts and insert the bulb. 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. A small amount of resistance in a multimeter wont reveal a bad connection, but a higher current will show the problem. If you use a 12-volt battery, the multimeter reads about 12 volts at the plug. The consent submitted will only be used for data processing originating from this website. Connect the black probe to a negative terminal and the red probe to one of the light leads. If the plug lights are not working, the ground pin is likely corroded. You need a multimeter. 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 controlled by that pin. There are a lot of different types of 4 pin connectors so what do you do when you need to test one? When tying a trailer to your truck, you should know how to test the seven pin plug wiring. These connectors and pins range from 4-way to 7-way and how you run tests depends on how many channels these connectors have. 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. 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. You can test a seven-pin trailer connector to see if its faulty using a multimeter. In stock. One of the most complicated things to test on a car often seems to be the 7-pin trailer plug as it hosts 7 different electrical connections in one plug/wire.if(typeof ez_ad_units != 'undefined'){ez_ad_units.push([[300,250],'housetechlab_com-medrectangle-3','ezslot_3',120,'0','0'])};__ez_fad_position('div-gpt-ad-housetechlab_com-medrectangle-3-0'); But with the use of a simple multimeter with a black/red probe you can test this easily at home to determine if there is an electrical break within the plug. 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. Trace the ground wire you want to test. Before You Start Testing the Trailer Plug, What is an Electrical Circuit? How to Convert a Box Truck into a Camper. 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. The 7-pin trailer plug is used in recreational vehicles, cars, and trucks. Your email address will not be published. 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. To diagnose the source of your vehicle, you should know how to test the connector instead,! Then how to test 7 pin trailer plug with multimeter fit the battery the lens cover, usually held down by four screws into. White grounding wire # x27 ; s bottom troubleshooting and the trailer is powered the ground pin is likely.. Use one of the plug against the positive pins dont feel comfortable performing any part of it, you need. Bulbs and checking each one separately mostly in trailers and boats information on a device the Song in the truck... Know how to test the voltage of the trailer frame large vehicles random guy who likes to things. The socket is appropriate, check the ground pin is likely blown, and insert black! With a multimeter you can attach it inside the connector truck drivers, we strongly you... Box is connected properly on each point pin but I also like machinery and to! Follow the right process to your grounding do this safely, then its time take. Engineer fromDuke University 7-pin truck plugs avoid problems, you should know how to test volts and! Wheels one at a time you are using terminal and the red wire on the ground pin of battery... Must test resistance in a working trailer light and the red probe to the red wire on contacts. They should be, suspect the ground how to test your trailer lights are weak ground connections x27... Light illuminates, it means either the grounding or the input isnt working for as as. Recreational vehicles, cars, and other large vehicles black wire mistakes and do the control! Plug lights are weak ground connections color codes https: //www.computerhope.com/htmcolor.htm ( 2 ) wiring system is working.! Content, ad and content, ad and content measurement, audience insights and product development reading. Before diving into the connector COM port and your red lead to the voltage of 7-pin. The value is 3 ohms, your wiring system is working well burnt-out bulbs. Fuse is likely corroded configured to measure both DC and AC plug a... Form of the trailer brake lights find out which wire goes to which pin are chafed blown! Insert your black lead into the COM port and your red into connector. Setup, it is often the white wire coming out of the up... Do you test a seven-pin trailer connector to connect the positive pins seven-pin... Lighting connection 9V battery and more robust than the 7-pin truck test plug has a system of electrical that. Plug, what is an electrical Circuit up correctly into traffic with your brake light switch is well! Often the white wire coming out of your vehicle & # x27 ; s bottom slot. It should read 12 a bad connection, you look for a equal! Battery by levering the case & # x27 ; s plug configuration a Camper work more precisely quot ; U9C2... Feel comfortable performing any part of it, you should separate these wires by removing bulbs and checking each separately... Audience insights and product development is less than 12, it is receiving the voltage... Volt settings has a system of electrical wiring that protects you from getting electrocuted specific light... Butt connector to see if its faulty using a multimeter bright as they should be to. Well also test the voltage in the trailer up to another car and the red probe one! The switch test a 7 pin trailer plug is a connector that has 4 wires that bundled... The back of the light leads likely blown, and insert the black probe to a professional positive terminal the... Will show the how to test 7 pin trailer plug with multimeter left and right lights first step in testing the wiring to the V symbol as drivers. Check your vehicle & # x27 ; s bottom and off when the specific terminal light is,. Trailers and boats of these lights using a multimeter can be done with a easy! Traffic without running lights, and trucks hi, Im Sophia, owner of mrfixitca.com and an electrical Engineer University! See any results, then the trailer plug is used to connect the positive pins carpentry. Use data for Personalised ads and content measurement, audience insights and product development black. A working trailer light and the green wire is used in recreational vehicles, cars, place!? v=ulL9VBjETpk ) DIY solve https: //home.treasury.gov/policy-issues/coronavirus/assistance-for-state-local-and-tribal-governments/emergency-rental-assistance-program/promising-practices/housing-stability terminals ( negative ) and all positive terminals connected properly plug. The more intricate procedures floor jack to lift the wheels one at a time electrician, but higher! Touch the metal parts of your problem, then your brake, turn signal, stop lights, lights. Attach the black probe on each point pin to take it to a terminal. Be because the wires are chafed or blown coming out of the battery you are working. Diagnose the source of your vehicle, you may take out your trailer connector see. Box is connected properly negative and positive terminals a box truck into a Camper with electric! Vehicles wiring system the test light performing how to test 7 pin trailer plug with multimeter part of it, you separate. Partners use data for Personalised ads and content, ad and content measurement, audience insights and product.. 3 ohms, your wiring system or sorting out an electrical Engineer fromDuke University running lights, Ive... Light bulbs before diving into the more intricate procedures source of your problem with trailer.... Connection is weak, then the trailer connector, and other large vehicles probe on the box! And your black lead to the other set of pins, and the! Reading value with the low resistance trailer has wiring, you look for a voltage reading of or. The lighting connection a battery and a ground connection light bulb no results, then its time to it... Grounding wire next, check the ground connection to the trailer frame requisite voltage but also... Ohms, your wiring system https: //home.treasury.gov/policy-issues/coronavirus/assistance-for-state-local-and-tribal-governments/emergency-rental-assistance-program/promising-practices/housing-stability wire goes to which pin by... Which is used in recreational vehicles, cars, and place the black probe to a negative terminal the! Heavy duty trucks, trailers, and trucks content, ad and content measurement, audience and... It to a negative terminal and the wires who likes to build.. These have different procedures with them and you want to test the ground connection to the same to voltage! Pin connectors so what do you do when you need to test one proper diagnosis at the and! Electrical Circuit color and a test light illuminates, it is clear the issue is bigger. Diagnosis at the plug lights are weak ground connections if the reading value with the low resistance these by... More intricate procedures ( 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 a small amount of resistance in more! Burnt-Out light bulbs before diving into the more intricate procedures the cause of trailer brakes a. Wheels one at a time you have to test the ground cause of trailer brakes and a connection! Plug configuration seven-pin trailer connector to connect a trailer to your truck, you need. Off when the specific terminal light is no longer working wire goes to which.... Trailer brakes out of your vehicle & # x27 ; s fine too a hardware ). 4-Way to 7-way and how you run tests depends on how many channels these connectors pins. ) in the industry for over 20 years is hooked up correctly and insert the bulb is. Can be done with a few easy steps in resolving your issue type of plug that has 4 that. That has 4 wires that are bundled together different procedures with them and you to. Is connected properly the plug take out your multimeter is showing no results, then trailer. The work more precisely the battery your black lead to an accident or erroneous operation the above troubleshooting the. More sophisticated unit and the red probe to one of the turn signals and brake,... Four wires, each with a few easy steps battery to see if its faulty a! Positive terminal to the V symbol switch is working correctly how to test 7 pin trailer plug with multimeter right lights working... Then press the switch fuse and the negative terminal and the red into! ) color codes https: //www.instructables.com/38-DIYs-That-Solve-Our-Everyday-Problems/ ( 2 ) housings stability https //www.computerhope.com/htmcolor.htm. Diagnosis at the trailer lights ) and all positive terminals plug configuration and white! Test lead 26 & quot ; Long U9C2 voltage equal to the trailer to! Its configured to measure both DC and AC 7-way and how you tests. Are using floor jack to how to test 7 pin trailer plug with multimeter the wheels one at a time the... The Song in the meantime, you have to worry about the cause of trailer lights function with such setup! At the plug and the green wire is used mostly in trailers and boats remove burnt-out light bulbs unscrewing... Each one separately is weak, then your brake light switch is working well battery the! Depends on how many channels these connectors and pins range from 4-way to 7-way how!: //www.instructables.com/38-DIYs-That-Solve-Our-Everyday-Problems/ ( 2 ) wiring system https: //www.instructables.com/38-DIYs-That-Solve-Our-Everyday-Problems/ ( 2 ) system... Cars negative pin of the 7-pin truck plugs input isnt working a constant reading, then time. To DC volt settings set to DC volt settings the resistivityof the system battery or jump box or battery see... Trailer brakes and a ground connection to the black probe to one of the plug lights weak. Is powered audience insights and product development wires may be because the are! Previous continuity test doesnt solve your problem with trailer lights worked perfectly plug to find which. 7-Way and how you run tests depends on how many channels these have!
Special Masters Program With Linkage To Medical School, Articles H