Glow Plug Relay

HOW TO DETECT THE GLOW PLUG RELAY FAILURE

Malfunction of the glow plug relay is simple to check on your own. For this purpose you need a multimeter or a test lamp.

You have to connect the tester probes or the lamp contacts to the relay control pins and apply 12 volts to it. If the relay is operating correctly, the lamp will light up and the tester's readings will change. Besides, you will hear a distinctive click. Absent light from the light bulb, no click and the unchanged tester readings indicate that the relay contacts do not close.

After that, switch the multimeter into resistance mode and measure the resistance between the relay coil winding pins. If the gauge shows a breakage, the component requires replacement.

Two-stage glow system relays are installed on many modern cars. In this case, you should test the resistance between the two pairs of control contacts as described above.