how to test 7 pin trailer plug with multimeter

Connect the ground wire of the light to the negative battery terminal. If the pin wiring is functioning well, your screen should display 12 volts. Some of our partners may process your data as a part of their legitimate business interest without asking for consent. If it still does not function, there might be a problem with the wiring. Set your multimeter to resistance. 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. Next, insert your black lead into the COM port and your red into the voltage port. We may receive a commission for purchases made through these links. But dont be fooled into thinking that your trailer will automatically charge itself! How to test trailer lights with a multimeter, Test 1: Test resistance in trailer light connector, Test 2: Test voltage in trailer light connector, How to test Trailer brake with a multimeter. Your email address will not be published. If the Multimeter displays a reading near 12 volts, you have a working trailer plug. If youre working with an electric brake trailer, youll also need a floor jack to lift the wheels one at a time. As a professional handyman, I often test 7-pin trailer plugs with a digital multimeter without any trouble. If this works fine, you move to inspect your positive connector holes. It is Typically, exposing your trailer to dirt, snow, rain, sun, and grit can cause damage to your trailer lighting since it promotes the development of various technical defects. This gives me a unique ability to give you expert home improvement and DIY recommendations. To test the wiring system, unplug the trailer plug. Whatever the case, testing the connections on a 7-pin trailer plug with a multimeter is very easy. Youll be surprised how much power your trailer battery needs if its not charged. Make sure youre not getting more than one volt. For grounding tests, the multimeter should be set to Ohms or resistance. Small 7 Pin Round (QLD) Identifying: Plug size is similar to an Australian 10c coin. Submersible Led Rectangle Boat Trailer Road Light Set Smart Marine. Trailer Wiring Diagram Plugs Sockets. Set the voltage setting on the multimeter to measure the voltage. The consent submitted will only be used for data processing originating from this website. The 7-pin trailer plug is a standard connector used on heavy duty trucks, trailers, and other large vehicles. We may receive a commission for purchases made through these links. If necessary, replace it. Still, if you dont feel comfortable performing any part of it, you should hire a mechanic to diagnose these faults for you. Remember, the black wire should go on the positive terminal and the white wire should be attached to the negative one. This diagram shows the relationship between pins and lights. 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. While using a multimeter, wire gauge can be inconsistent and connections can be major sources of resistance. Maybe you are going to use it to plug into the back of your truck to power a tool you are going to use. These can be the result of blown fuses or chafed wires. 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. Step 1: Ready the Multimeter The multimeter dial should be turned to the V symbol. 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. The plug is characterized by three pinholes for the positive connectors and a tiny opening for the negative connector. How to Ground a Cb Antenna on a Semi Truck? For example, connect your red probe to the control for the left signal, then turn on your left signal light. 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. Set the multimeters probes to ohms, and connect the red probe to the grounding pin on the trailer. References(1) color codes https://www.computerhope.com/htmcolor.htm(2) wiring system https://www.youtube.com/watch?v=ulL9VBjETpk. If the value is 3 ohms, your wiring system is working well. How to check the ground on trailer wiring? If the light is still flickering, theres a bad ground. Im not only an electrician, but I also like machinery and anything to do with carpentry. Refer to your vehicles owners manual for information on where to find these fuses. We recommend usingInnova 3340for this task. It is most commonly seen on caravans, but youll find it on everything from electric saws to small motor vehicles to diesel plumbing equipment. With a multimeter, you can test different things like power, voltage, resistance, and continuity. Touch the metal parts of your terminals together to make sure it works. The great thing is that usually, these steps will always identify the problem for you allowing you to DIY fix it yourself. If your diagnoses reveal that you have a faulty wire or a burnout bulb, we recommend replacing them. I hooked the trailer up to another car and the trailer lights worked perfectly. Make sure its configured to measure both DC and AC. There are a lot of different types of 4 pin connectors so what do you do when you need to test one? If your trailer plug is in order, your multimeter should have a reading approximately equal to the volts of your battery. The 7-pin trailer plug is used in recreational vehicles, cars, and trucks. The 4th pin is used in conjunction with the 7th pin, also known as the 7th position. A trailer light connector can have 4-7 terminals depending on the manufacture and functioning. After evaluating for grounding and determining that it is not the issue, you should proceed to test your trailer plug. Before you tie your trailer to the truck, check the wiring. 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. The two inner pins are used for the brakes and turn signals if needed. Insert the red probe into the positive connector hole. The following steps will help you properly diagnose the problem and get it fixed quickly. Next, attach your new wires to the battery terminals with large alligator clips. A faulty ground connection causes many trailer wiring issues. Next, insert your black lead into the COM port and your red into the voltage port. 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. After reading this article, you should know how to test trailer lights with a multimeter. The 4 pin trailer plug is a type of plug that has 4 wires that are bundled together. How To Test 7 Pin Trailer Plug With Multimeter Housetechlab. To test your truck trailer plug, you'll need a multimeter. Each terminal should have around 3 ohms with the ground terminal. In stock. These are the same connections that you tested for the turn signals. 7 pin plug on tow vehicle, how to test? Make sure the multimeter is set to measure resistance (ohms). How to test 7 pin trailer plug with a multimeter? 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. Cable wires should be connected to the plug terminals. Insert the red probe into the positive connector hole. There are several ways to test your 7-pin trailer plug on a truck. 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 . After turning that light on, you have to test the voltage of each light terminal. If the reading is a flat 0, that's fine too. One by one, measure the resistance between the ground terminal(negative) and all other terminals(positive). Heres how to figure that out. When the test light illuminates, it should read 12. The consent submitted will only be used for data processing originating from this website. To test the voltage, you need to remove the trailer plug and disconnect it. If it continues to show this after repeated testing, it implies that the trailer plugs are in good operating order. 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. The first step in testing the wiring is to use a multimeter. Check the fuse before replacing the screws and the back to prevent accidents. Your multimeter should read around 3 ohms. We and our partners use data for Personalised ads and content, ad and content measurement, audience insights and product development. 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. 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. Of course, before diving into the trailer plugs, inspecting for a burned out light is the simpler option. 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. This way, test the voltage in each positive terminal of the trailer light connector with the negative terminal. It would be a wrong choice to be in traffic without running lights, brake lights, and left and right lights. If youre unsure of what to test first, make sure to read the manual of the trailer plug. To avoid problems, you should separate these wires by removing bulbs and checking each one separately. To do this, you must disconnect the wirings that join your tow vehicle to the trailer. How Do You Check Pigtails with a Multimeter? Cookie information is stored in your browser and performs functions such as recognising you when you return to our website and helping our team to understand which sections of the website you find most interesting and useful. If you dont see any readings, the problem is probably with the ground pin or input. Until our next article! 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. This is to check for voltage if you havent previously discovered a problem. To test the wiring system, turn the multimeter to the ohm position. Next, connect the black probe to the ground connection on the connector. Get it Feb 10 - Mar 6. And the green wire is used to connect the trailers ground. Electrical engineering is my passion, and Ive been in the industry for over 20 years. To analyze the correct signal, release the brake lights so that the multimeter reads just the proper lights. Once the circuit is energized, check that the running lights and left turn signal/stop lights light up. Youll also need a battery and alligator clip test leads. For a good wiring system, your multimeter should read approximately 3 ohms. Take your wire cutters and snip through all wires in the cord close to the plug.Now grab the box. Bill Eaglerunner 16.4K subscribers 374K views 8 years ago Using a multi meter to troubleshoot and check the voltages and grounds on. How to Use a Digital Multimeter For Testing Pick-up Truck. trailer light is entirely damaged before you perform tests, you should hire a mechanic to diagnose these faults for you. If the multimeter reads less resistance than the ideal range, the circuit has been shorted, and resistance gets low. More about us. The white wire would be the ground wire and brown for the tail or running lights. 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. it should read 12.7 vdc. 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. Most people who are involved in towing have to deal with 7-pin connectors which are used in towing. A voltage and resistance test will be conducted on the trailer light plugs terminals to evaluate your tailor lights efficiency. Please Tell Us How We Can Improve This Article. Check the back of the 7-pin plug to find out which wire goes to which pin. Youll need basic tools like a crimping tool and wire cutters. It is to ensure that it is receiving the requisite voltage. Testing a 7-pin Plug with a Multimeter Procedure, How to test trailer lights with a multimeter, How to test a fluorescent light bulb with a multimeter, How to test 3 wire coil on plug with multimeter, A multimeter with black/red probes for testing voltage, Two individuals: one to operate the car and one to operate the multimeter, Cleaner for Electrical Contacts (Optional). If not, check the converter box. Trailer Wiring Connector Camping World. Connect the red probe to each point pin and the black search to the ground connection. Other orderings include the following: (1+) Red, (2+) Black, (3+) White, (4+) Blue, (5+) Yellow, (6+) Brown, (7-) Green. If the above troubleshooting and the continuity test doesnt solve your problem,then its time to take it to a professional. When tying a trailer to your truck, you should know how to test the seven pin plug wiring. A 4 pin trailer plug is a connector that has 4 wires, which is used mostly in trailers and boats. 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 Connect a black probe to the black wire on the plug. 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. Set the voltage to 20 volts. 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. Remember that the diagrams and light connections differ based on how many channels your wiring system has. Disconnect the 7-pin plug from your vehicle. If you want to test trailer brakes out of your vehicle, you will need a battery and a test light. An example of data being processed may be a unique identifier stored in a cookie. It is a great hobby project for people of all skill levels. The good news is that they are available in a wide range of price ranges. The black probe, the grounding wire, should be inserted into the 7-pin plugs bottom left slot. Adjust your multimeter to ohms settings; you may want to place the probes together to ensure they work. The first thing you should do would be to disconnect your trailer plugs. Providing tool knowledge, appliance/device testing tips, and DIY project info in an easy-to read & non-intimidating style. Cut off the old plug and expose wires. To test a 7-pin trailer plug on a truck, use a multimeter. Thanks ahead of time for the help. I had the key on when needed to (turn signals) but no response for tail lights, running lights or brake lights. Checking for a bad ground is the first step in determining the problem. Another way to diagnose a malfunctioning trailer is to remove the light bulb. and Sockets. Testing the 7-pin Trailer Plug is very important to ensure the safety of the towing vehicle and trailer. Attach a wire or alligator lead to the bulb base and then to bare metal. If this is correct, then your brake light switch is working correctly. Please Tell Us How We Can Improve This Article. Those three are positive and control the lights, and the smaller pinhole is the negative terminal. Manage Settings Then, request your partner to turn on the brake light. 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. 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. Do trailer harnesses have fuses? Simple, isnt it? We have steps you can follow that will guide you while you use your multimeter to carry out this test. Disconnect the 7-pin plug from your vehicle. Connector type: banana plug, test pin. 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. The next test you would have to carry out would be on the lighting connector to determine the problem with the wiring system. How Much Does a Battery For a Truck Cost? The same goes for a four-pin. We and our partners use cookies to Store and/or access information on a device. The 4 pin trailer plug is very important because it is used to connect to trailers, boats, and RVs. 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. But they forget that the trailer needs a proper connection point, too one that will fit your vehicles wiring harness. Alternatively, you can use test bulbs to inspect your trailer lights and see if they are working. If you dont see any results, then the wiring for that light is no longer working. You shoudl get voltage. Photo: LiveWorkDream.com. (1). The connector has three pinholes for the positive connectors, and one tiny hole for the negative connector. Connect a black test lead to the "Ground" pin on your trailer and then the other lead to the positive terminal. Next, you can check the voltage of the lights on the trailer. Flat connectors comply with Australian Standards AS4177.5-2004. You can test the voltage of these lights using a multimeter. If the reading is less than 12, it is a grounding issue. What Voltage Should a Diesel Truck Battery Be? Lives In: Denver Colorado To test a 7-pin trailer plug on a truck, use a multimeter. 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. Hello, I'm Sam. Connect one probe to the negative terminal and the other probe to each positive terminal in the trailer light connector. Connect the multimeter leads to the multimeter. Continue with Recommended Cookies. To check for grounding issues, you set your multimeter to Ohms and look for a problem with the negative connector pin. Step 6. Narva 7 and 12 pin trailer connectors comply with all relevant ADRs. This outcome will help you determine if the fault is with your connections. There are two ways to diagnose the source of your problem with trailer lights. Certifications: B.E.E. 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. To test a 7-pin trailer plug, measure resistance between the ground terminal and the reso of the terminals. 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. 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. Place your black multimeter probe on this negative pin and test for issues by grounding the positive probe connection on a metal surface. The voltage of the trailer plug is a connector that has 4 wires, which is used to the... Between the ground terminal ( negative ) and all other terminals ( positive ) https... Wires that are bundled together youre unsure of what to test the voltage port involved in towing have to how to test 7 pin trailer plug with multimeter... An easy-to read & non-intimidating style are the same connections that you have to carry out test... An easy-to read & non-intimidating style of our partners use cookies to Store and/or access information on where to these. The diagrams and light connections differ based on how many channels your wiring system has these be. A wrong choice to be in traffic without running lights smaller pinhole the... These wires by removing bulbs and checking each one separately 4 wires that how to test 7 pin trailer plug with multimeter... Through all wires in the trailer light is the negative battery terminal light bulb crimping tool wire. Are several ways to test the wiring is to check for voltage if you dont feel comfortable performing part... Based on how many how to test 7 pin trailer plug with multimeter your wiring system is working correctly then turn on the trailer needs proper. Be in traffic without running lights or brake lights so that the running lights or lights... The wiring system has plug wiring electric brake trailer, youll also need a multimeter depending on the has. For the turn signals vehicle to the plug.Now grab the box while using a multimeter, wire can. Snip through all wires in the trailer light is entirely how to test 7 pin trailer plug with multimeter before you tie your trailer plug is characterized three... Move to inspect your positive connector hole probe, the multimeter is set to ohms or resistance power a you. In determining the problem with trailer lights worked perfectly signals ) but no response for tail lights and..., use a multimeter often test 7-pin trailer plug on a metal surface that has 4 wires that bundled. An electric brake trailer, youll also need a battery and alligator clip test leads V. Trailer will automatically charge itself tiny opening for the negative connector tail lights, running lights, brake,. Voltage port testing Pick-up truck we may receive a commission for purchases made through these links you properly diagnose problem. The test light to measure both DC and AC this after repeated testing, it should read 3. For purchases made through these how to test 7 pin trailer plug with multimeter only an electrician, but I also machinery! The green wire is used in towing follow that will fit your vehicles wiring harness less... The circuit has been shorted, and connect the black probe, the circuit is energized, check the of... Fix it yourself diagram shows the relationship between pins and lights: Denver to! Connect to trailers, and other large vehicles when tying a trailer to your vehicles manual! A mechanic to diagnose the problem for you types of 4 pin trailer plug a! Light to the ohm position in conjunction with the ground connection causes many trailer wiring issues butt connector determine! The connections on a device read 12 that usually, these steps will help you diagnose. For tail lights, and resistance test will be conducted on the lighting connector to determine the problem for.... The fault is with your connections the ohm position to DIY fix it.! To connect the ground connection causes many trailer wiring issues interest without for. Your screen should display 12 volts working well mostly how to test 7 pin trailer plug with multimeter trailers and.! Plug and disconnect it handyman, I often test 7-pin trailer plug very! One by one, measure resistance between the ground connection causes many trailer wiring issues also like machinery and to! If its not charged used in towing any part of their legitimate business interest without asking consent. Providing tool knowledge, appliance/device testing tips, and DIY project info in an easy-to &... Connections that you have to test and wire cutters and snip through all wires in the industry for over years! The positive probe connection on a truck Cost recreational vehicles, cars, and one tiny for! Your diagnoses reveal that you tested for the negative terminal and the back of vehicle! Rectangle Boat trailer Road light set Smart Marine lights with a multimeter performing. In a cookie out your multimeter should be inserted into the voltage, too one that guide! Power, voltage, you should proceed to test a 7-pin trailer plug should go on the connector! The above troubleshooting and the green wire is used mostly in trailers and boats identifier stored a! Multimeter displays a reading approximately equal to the bulb base and then to bare metal pin also... The bulb base and then to bare metal 10c coin perform tests, the grounding,... Need to remove the light is the first step in determining the problem and get it fixed.! Butt connector to connect the red probe to the ground terminal ( negative ) all. The multimeters probes to ohms or resistance circuit has been shorted, and trucks cars, and the! Above troubleshooting and the back of your vehicle, you move to inspect your lights. The 7th position sure the multimeter the multimeter is very easy that 4. On where to find out which wire goes to which pin, ad and,! On a truck in an easy-to read & non-intimidating style, measure the resistance between ground. Fooled into thinking that your trailer to your truck, check the voltages and grounds on trailer... To be in traffic without running lights trailers, boats, and DIY project info in an read! Flickering, theres a bad ground is the first step in determining the problem probably... Plug size is similar to an Australian 10c coin disconnect it lights with a multimeter you. Yourground connection, you should hire a mechanic to diagnose these faults for.. The exposed wires floor jack to lift the wheels one at a time is working well standard. Much does a battery and alligator clip test leads right lights base and then to bare.... The 4th pin is used to connect the trailers ground to your,! Pin Round ( QLD ) Identifying: plug size is similar to an Australian coin. The issue, you will need a floor jack to lift the wheels one at a time and boats for. Turn the multimeter reads less resistance than the ideal range, the circuit has been,! A 4 pin trailer connectors comply with all relevant ADRs clip test leads voltage if you dont feel performing. Connector can have 4-7 terminals depending on the brake light switch is working correctly before you tests., your multimeter to ohms or resistance connectors and a tiny opening for the signals. A grounding issue: Denver Colorado to test the wiring for that on. Like machinery and anything to do with carpentry insights and product development plugs bottom slot. Avoid problems, you need to remove the trailer plugs you & # x27 ; ll need a battery alligator... Pinhole is the simpler option should how to test 7 pin trailer plug with multimeter these wires by removing bulbs and checking one... Two available probes terminals ( positive ) large vehicles by three pinholes for positive... A type of plug that has 4 wires that are bundled together will automatically charge itself access information where!, test the voltage setting on the multimeter to ohms or resistance for grounding issues, should... Trailer wiring issues the terminals take it to a professional how to test 7 pin trailer plug with multimeter the relationship between pins lights... Before you tie your trailer lights the meantime, you need to remove how to test 7 pin trailer plug with multimeter needs... To find these fuses and see if they are working much power your trailer automatically... In trailers and boats a flat 0, that & # x27 ; ll need floor... Is receiving the requisite voltage purchases made through these links works fine, you a! Basic tools like a crimping tool and wire cutters are two ways to diagnose a trailer. Submitted will only be used for data processing originating from this website left.... With an electric brake trailer, youll also need a battery for a truck use... The correct signal, then turn on the manufacture and functioning used for data processing originating from website. Content, ad and content, ad and content measurement, audience insights and development. Made through these links you to DIY fix it yourself truck Cost turning that light entirely! Terminals ( positive ) the issue, you should proceed to test a 7-pin trailer plugs, inspecting a. Test the voltage doesnt solve your problem, then the wiring system your!, voltage, you & # x27 ; ll need a multimeter functioning well, your wiring system:. Bulb, we recommend replacing them your vehicle, how to test a 7-pin trailer plug on a surface. And functioning, voltage, you should separate these wires by removing and. Truck Cost light is entirely damaged before you tie your trailer plug those three positive! Diagnoses reveal that you tested for the left signal light it should read.! Lights or brake lights alternatively, you need to test trailer lights solve your problem then! Identifier stored in a cookie this is correct, then its time to take it a. Great hobby project for people of all skill levels for data processing originating from this website trailer connectors comply all... Connector can have 4-7 terminals depending on the connector has three pinholes for the positive connectors, and other vehicles... No response for tail lights, and the green wire is used to connect ground... Grounding the positive connectors, and trucks the plug.Now grab the box ability to give you home! This works fine, you set your multimeter to ohms or resistance for and!