Glow plug relay - Diesel Forum

nealtahoe · 03-08-2010, 07:36 PM

I got a new glow plug relay. I connected the wires that were on the big post the same way that was on the old glow plug relay. I did the same with the small post. Have current to all post but one of the big post. Tried a cold start, turned on the ignition, wait to start engine light on, and check the post that did not have power. Still does not have power.
Whats up?

Oh, I have put in all new glow plugs

RT · 03-08-2010, 07:54 PM

One of the small posts should have 12V+ all the time, the other is grounded by the PCM when you initially turn your key on. That closes the relay between the large positive lead, and the large lead that goes to your glow plugs.

WayneB · 03-08-2010, 08:16 PM

FYI: Your GPR and Wait To Start Light are not on the same circuit. You can have a Wait to Start Light and not have the GPR on and visa vera. Watch the voltage Gauge, when the glow plugs turn off you will see it jump up a few volts.

If your engine is warm your GPR will not turn on.

Wayne B

Alaskapsdvan · 03-08-2010, 08:44 PM

I have learned over winters to watch that needle or the scanguage , when the glow plugs are done, the needle will climb and the scangauge will come on, then it is ready to start..
If the engine is cold that all takes longer, when it is warm shorter... when hot no time at all...

428INTERCEPTOR · 03-08-2010, 09:38 PM

Did you double check to ensure it's a 12V, not a 24V. I chased my tail for most of a Saturday chasing wires until I discovered I ordered the wrong Stancore relay....the 24V one.

Opps....