Check a Relay Switch
The first step in troubleshooting a relay switch is to check the coil. You can use a multimeter to test the resistance between the coil pins with a test light. If the resistance reading is too high or too low, it means that there is a short circuit or an open circuit between the coil pins. Otherwise, it means that there is no short circuit.
You can also check the terminals for corrosion and extreme heat. Relays are made of plastic, and if the terminals are overheated, they will melt or distort. A quick video of the relay’s internal circuit can help you narrow down the problem. Also, modern relay switch are equipped with an LED to indicate whether they are on or off.
If the coil is energized, the relay will switch the circuit between the terminals. If it is not, the spring will pull the armature back to ‘at rest’. Likewise, if the coil circuit is off, the relay is not energized. When you apply voltage to the relay, the coil circuit generates a magnetic field around the contact, which completes the high-current circuit.
How to Check a Relay Switch
Failure to switch is a common symptom of relay malfunction. A short circuit can be a major cause. A burnt-out coil can also be a sign of a more severe issue. A high amount of current in the circuit can also damage a relay. Excessive voltage or carbon buildup can cause the relay to fail. This will affect its life span.
The first step in troubleshooting a relay switch is to check its AC control voltage. The AC Control Voltage will help you determine whether the relay is in good condition. The light bulb should be on when you close the switch, while it will be off when you open it. Make sure you have a multimeter ready for this test. If the multimeter reads “OL”, it means that the relay has been damaged.
Relays are electromechanical devices that switch high-powered circuits. The contacts in relays switch between two different states, called “load” and “decade.” Relays are made of metal and can be damaged or faulty. Therefore, it is imperative to maintain the contact loads of relays to ensure proper operation.
To check a relay, you will first need to locate the relay. You can usually find it under the dash or in the engine bay. If you cannot find it, consult your vehicle’s service manual for a wiring diagram. You can then pull the relay out and examine the pins.
You can also use a multimeter to check the resistance of a relay. A multimeter should be set to the “Ohms” setting. If the multimeter reads infinite, the relay needs replacement.
