how to test a relay without a multimeter

Connect your test light across the ground and the switch terminal. If the multimeter reads Open or Out of Range, it could mean a defective coil winding. First, be cautious and replace your main relay with the necessary tools. If the Buzzer does not ring this means that your coil is faulty. This makes them ideal for pinpointing the general location of a cable break within the circuit, for instance. Testing pins randomly without knowing the pin configuration is possible, but if the relay is damaged, results may be unpredictable. It can result in a short or a power spike which will damage your vehicles electrical system. Sometimes overheating prevents proper current flow in a circuit. The consent submitted will only be used for data processing originating from this website. The next step is to put the tip of the two Multimeter leads on both solenoid's heft depots. This is one of the main reasons as to why most electricians prefer specialized continuity testers over multimeters. This article was co-authored by Ricardo Mitchell. For instance, a continuity tester provides a great way of seeing whether a lamp wiring is intact or whether the inner mechanism of a disconnected switch is operating accordingly. Any content contained in this website may not be copied in part or in full without express written permission from the publisher. Related Post: How To Test A Relay With A Battery (With Pics): The Easy Way. This means that the current path is open and there is no connection, indicating a faulty relay component, linking mode in the DMM also emits a beep when it detects a closed current path, indicating that there is a link between the test leads. Test leads: 5. When testing for continuity using a specialized tester, an indicator will be activated when a circuit is thoroughly established. Connect the 9V DC as control voltage to the input and connect a switch to the terminal "3" and "4". Related Post: How To Wire A 4 Pin Relay For Horn & Lights With Diagram. Before you start making any test, first visually inspect the relay, and look for corrosion and carbon deposits. First, test the coil in the primary side of the relay to see if the circuit is working. How to test a relay without a multimeter? It consists of a coil, armature, and two contacts: Normally Open (NO) and Normally Closed (NC). Check for proper resistance in the switch. It can damage the ohmmeter while testing the resistor when the current is flowing. Take off the test light and set your multimeter to read DC. Do not use an ohmmeter when the high amperage path is connected to the source of the power. Here, Im referring to the amperage path ofit. Pull the wire connectors off of the capacitor with needle-nose pliers. "This article has been very valuable in helping me diagnose a relay problem with my truck. Apart from this you can set the multimeter to the Continuity scale and listen to the beeping sound. Therefore, the circuit is opened. Testing continuity without a multimeter As previously mentioned, we can use testers in testing continuity as an alternative for a multimeter. Make sure you have a good working horn. Smoothly grasp and pull the relay upward by hand while slightly wiggling the relay for gentle extraction. First of all, check the relay location. Certified Automotive Diagnostic Technician. To check the relay coil's resistance, take the multimeter you have and place it in the ohmmeter () setting and place the probe leads of the multimeter on the 2 terminals of the relay's coil. The comterminal is usually labeled as end 30 in its wiring diagram. Thank you for this and. You only have two options if youre confident that theres a problem with your relay, and both require the use of an ohmmeter, test light, etc. Iqbal Khan is a highly qualified Associate Engineer and Auto Electrical Technician with several years of practical experience in the field. ! This article has been viewed 825,674 times. There are several benefits of continuity testing such; Although you will end having multiple separate pieces of equipment, a specialized continuity tester is a big bonus in your tool kit. Find a safe location in your garage or workshop to work with the automotive relays. Here's How To Test a Relay Let's get started! If the relay does not make a clicking sound, then proceed to the next step. How to test a 4-pin relay with a multimeter The loop path has two terminals called 85 and 86 s, where the first endof the relay (85) is designated as a negative end and is given ground power, whereas end 86 is designated as a positiveand is given a hot power source. When you remove the jumper, the light should go off. Do not work with relays or anything requiring electricity in areas where explosive or flammable gases, such as gasoline or other fuels, are present. Ricardo Mitchell is the CEO of CN Coterie, a fully licensed and insured Lead EPA (Environmental Protection Agency) Certified construction company located in Manhattan, New York. To view the purposes they believe they have legitimate interest for, or to object to this data processing use the vendor list link below. After that, connect the switch pins with the leads. The relay isolates the high power circuit, helping to protect the lower power circuit by providing a small electromagnetic coil for the logic circuit to control. The consent submitted will only be used for data processing originating from this website. Some relays, depending on their size, may also have this information printed directly on the body of the relay as well. If it is not functioning properly, the DMM will show high resistance or no current flow, indicating that the switch is not closing. All the NC contacts should read 0 ohms, or 0 resistance, while the NO contacts should read infinite resistance. Relay TESTING and REPLACEMENT CarsNToys 181K subscribers Subscribe 7.6K 2.6M views 6 years ago . Unlike most testers, the continuity testers are always used when you turn off a circuit or on wires and devices that are disconnected from a circuit. Also, refrain from tampering with the relay. To test a relay without a multimeter, attach the coil terminal in the relay to a battery. Using the incorrect relay can lead to power surging or a short, damaging the vehicles electronics. For example if the resistance is 320 and the tolerance value is 10% , then we should get resistance values somewhere between 288 to 352. Remove the positive jumper wire and return the voltmeter to ohm settings. It means that terminals 85 and 86 are fine which produces a clicking sound. First of all, identify the relay you want to test with the help of the image given below. By using our site, you agree to our. He has been working as a car mechanic for over 10 years, and the majority of them specialized in advanced car diagnostics and troubleshooting. CN Coterie specializes in full home renovation, electrical, plumbing, carpentry, cabinetry, furniture restoration, OATH/ECB (Office of Administrative Trials and Hearings/Environmental Control Board) violations removal, and DOB (Department of Buildings) violations removal. If the ohmmeter checks for resistance on the pins 30 and 87 paths by its abbreviation, OL, which means that Open-Loop or Open Load or with very high resistance. Were committed to providing the world with free how-to resources, and even $1 helps us in our mission. Set your multimeter to ohms mode. The third way is to use a voltmeter to see if there is voltage coming from the relay. When testing for continuity, they will vibrate or click in the presence of voltage. The resistance of the coil circuit is approximately 50 to 120-ohm value between coil circuit pins. The LED flasher can [], Are you in search of a reliable and high performance but simple 5v to 12v boost converter circuit? Include your email address to get a message when this question is answered. Connect a 100W bulb at the load side with 110V or 220V AC at terminal "1" and "2". General and most common faults found in starter relay are at: i) Coil: (conditions- burnt coil, broken connection), ii) Movable contact: (condition- lost its movability, carbon covered/rusty contact due to sparks), Pinout diagram with the notation: NC: Normally closed NO: Normally opened COM: Common C1/C2: Power supply to the coil, (just keep in mind that types of relay differ only on the basis of the number of terminals but the actual principle of working is same i.e principle of electromagnetism). Read the result off the multimeter display. No. Whenit is energized, pins 30 and 87 will start to have linked. The second halfis called a load path or high amperage path. It could be located under the dash or in the engine bay, depending on what it's controlling. Related Post: Car Relay Guide: What it is & How A 12V Relay Works. If it is less than 50 ohms, it could be faulty. ", "This helped me understand a little more about how to test my cars relay. Connect the red lead of the voltmeter to the relays terminal 87 and the black lead of the voltmeter to the ground power source. Here's a step-by-step guide on how to do it. This reading should show the same as your batterys voltage, typically 12V. Your email address will not be published. Im not only an electrician, but I also like machinery and anything to do with carpentry. They are present in almost any vehicle. These accessories can range from the main computer PCM (powertrian control module), radiator fan, fuel pump, door locks etc. His passion for auto electrics and his ability to solve technical problems quickly and efficiently is what sets him apart. If you have identified the type of relay with the help of the above image, then just follow one of the following methods : The first method is by using a multimeter Set the mode of multimeter to the Continuity mode, Step1: Connect the two probe of multimeter to the coil terminals( C1 & C2) as shown. How to Test a Relay A relay is switch that utilizes an electrical trigger signal to activate. It comes under the hood, under the dashboard, or side kick panel. Proceed to connect the red lead to pin 30 and the other black lead end to be connected to pin 87a. Below is how to carry out the tests. If it is working properly, the DMM should show low resistance or low current when activated, indicating that the switch is closing. The high amperage path contains three pins 30, 87, and 87a. Step1: The two leads of the multimeter and the coil terminals 85- (C1) & 86- (C2) are connected to the multimeter; if the buzzer rings, your exciter coil is working. If a relay fails or is fitted incorrectly, it could fry your wires and possibly ignite a fire. Here is a video on how you can test a Relay with or without a diagram. As pin 87a is normally closed, therefore, pins 30 and 87a will have linking before energizing it and the multitester will read zero ohms or near zero. You might understand the basics, but its important that everything is replaced according to factory specifications. 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. Bad contact points can cause a voltage loss. document.getElementById("ak_js_1").setAttribute("value",(new Date()).getTime()); Your email address will not be published. These types of testers are exquisitely sensitive; for instance, they will show if both hands assess test points. . What is a relay? With the Multimeter Prepared, Test the Circuit Take the multimeter and attach it to a ground. In fact, you might have many of these supplies in your home garage right now. It can also simultaneously activate multiple systems, such as turning on the headlights while the windshield wipers run or extending a radio antenna when you turn on the stereo. In this tutorial, I will show you a step-by-step procedure on how to test an automotive relay without a multimeter. You should hear a clicking sound when the relay coil closes the connection. For this, you will have to switch the DMM to resistance mode. Now you have to identify the relays terminals. Whether that is a fuel pump relay, Starter motor relay, Car Air Conditioner relay, Headlight relay, radiator fan relay, or horn relay. Once you are through, you should always assess regularly the installation for any sign of damage and faults. Locate And Listen To The Clicking Noise Of The Relay. Before energizing the relay, connect the ohmmeter leads to a high amperage circuit of the relay. If everything is operating as it should, you want to move onto the switch. I tested my air condition micro relay. Electrician & Construction Professional, CN Coterie. I cover 3.4 and 5 pin relays and all you need is a 12v source, a multimeter and a test light. In general, a successful relay testing with a multimeter involves the following steps: One of the various methods to test a relay is through a digital multimeter. Take an appearance at the analysis on the display. They are also part of other applications, such as aviation and marine vessels. The loop circuit is the that when you pass the power, you hear a clicking noise. If everything looks good, you can connect the leads between the switch pins. In fact I made a test cable by cutting one end off of an old guitar cable and putting clip leads on that end. This problem would lead to melted wires or a car fire. Now, energizeit by giving power to the relays coil path. Next, you want to energize the relay with a 12-volt battery. How To Test a. How to test the relay with test light? The only tool required to check a relay is a multimeter. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/4\/4f\/Test-a-Relay-Step-2-Version-2.jpg\/v4-460px-Test-a-Relay-Step-2-Version-2.jpg","bigUrl":"\/images\/thumb\/4\/4f\/Test-a-Relay-Step-2-Version-2.jpg\/aid1420038-v4-728px-Test-a-Relay-Step-2-Version-2.jpg","smallWidth":460,"smallHeight":345,"bigWidth":728,"bigHeight":546,"licensing":"