Share this...

Pinterest Linkedin Reddit

How to test any car relay. Relay testing hack you can do in your car. I will show you many different ways to test a car relay with a battery, jumper wires, and a power probe.

Subscribe to my youtube channel here: https://goo.gl/j1pCfn

For the most common automotive fixes to the most common car and truck problems. DIY auto repair to help you save money.

This video goes over how to test a cars relay. We will be testing the relay out of the car with a battery, jumper wires, and a power probe. I will show you how to test a 3 4 and 5 pin relay.

RELAY TESTING STEPS:

PINS:

Control Circuit (shows resistance 50 to 120 ohms)

86 Power In (example: from Ignition Key)

85 Ground

Switch Circuit that controls Accessory Item (ie STARTER MOTOR)

30 Power In HOT

87 Power Out

RELAY TEST 1

Set meter to 200 ohms,

Test for resistance between 85 and 86 (Circuit with COIL)

Acceptable range 50 to 120 Ohms, example 70 ohms is GOOD

BELOW 50 or ABOVE 120 ohms = Relays is BAD

RELAY TEST 2

Listen for a click

Supply 12 volts Power to 86

Ground to pin 85

You will hear 87 to 87a closing CLICK

RELAY TEST 3

Supply power to 86 and Gnd to 85, this circuit ENERGIZED

now check for resistance between pins 30 and 87

Set meter to 2000 OHMS

Look for LITTLE or 0 resistance

RELAY TEST 4 with TEST LIGHT or light bulb

Supply power 12 volts to 86 and Gnd to 85, this circuit ENERGIZED

Supply 12 volts to pin 30

Ground your test light and TOUCH 87 to see light come on.