Contents
How much voltage does a starter relay need?
Working the starter switch should cause a drop from 12 volts to below 0.5 volts. If the voltmeter reading stays above 0.5 volts, look for a bad connection at the battery earth strap (at either end) or the engine-to-body earth strap. Clean and tighten the connections, and carry out the test again.
How do you test a starter relay?
Set your multimeter to be on the Ohms scale. Place one probe on the lead on the ignition circuit terminal and the other on the ground lead. The reading should be less than 5 Ohms. If it’s more than that, the starter relay is faulty and needs to be replaced.
What happens if starter relay is bad?
If your starter relay has gone bad, the electrical signal will never make it from the battery to the starter motor. As a result, your engine won’t turn over – no matter how many times you turn the key. A faulty relay often produces an audible clicking sound when you turn your car.
Can a car start without the starter relay?
Your Starter Motor Runs Continuously. In the discussion above, the car wouldn’t start because the faulty starter relay wouldn’t pass the signal to the starter motor. A starter relay may also fail the opposite way. As a result, the starter motor will continue to run even after your engine starts.
What do you need to know about a starter relay?
What is a Starter Relay? A starter relay is a small, electrical device found in the starting circuit of high-current motors. The relay is essentially a remote switch that controls a high-current circuit. In motor vehicles, a starter relay uses the small ignition switch current to close the much heavy-duty starter circuit.
What is the terminal number on a 12 volt relay?
Terminal/Pin number Connection: 85: Coil: 86: Coil: 87: Normally Open (NO) 87a: Normally Closed (NC) – not present on 4 pin relays: 30: Common connection to NO & NC terminals
What should the resistance be on a battery relay?
For extra credit, you can set a multimeter to measure conductivity (resistance) and connect it across relay terminals 30 and 87. When you touch 86 and 85 to the battery, the electromagnet pulls the switch contacts together, so the resistance between 30 and 87 should read essentially zero (under one ohm).
Which is the ground terminal on a fuse box starter relay?
The “S” terminal (or 85 terminal in some relays) receives a 12-volt signal from the car’s battery. A small current, usually less than 10 amperes, passes down the terminal and through the coil windings and through to ground. In the fender-mounted relays, this is the “I” terminal. In fuse box starter relays, the ground is terminal 86.