Testing gpr

[Falco]

I'm having major cold start issues...anything under 45 degrees and I cant start if I'm not plugged in. I read all the other cold start threads and it seems the problem is more than likely the GPR or the plugs themselves. I'm trying to understand exactly how the relay works so I know if I'm metering it out correctly. I'm assuming that the small terminals are the connections for the coil and when energized the large terminals should close. There is always 12VDC at the large terminal with the orange wire so I guess my question is, when the relay is energized I should have 12V between the large terminal with the brown wire and the negative terminal on the battery, correct?

[dray8165]

There is a great write-up on how to check your GPR in this thread:

GLOW PLUGS 7.3 WHEN TO REPLACE

[Falco]

Yeah i read that before i posted. I just want to make sure I understand how the relay is wired up

[robthebuilder]

small wires activate the solenoid, the large wires/terminals are input and output. the one closest to the turbo is going to the glow plugs.

[forddieseldoctor]

check voltage drop (connect your meter leads to the two big lugs) across the relay, should have no more than .5 volts. anymore and your relay is bad.

[NCHornet]

When the key is first turned on you should have 12 volts on both large terminals. Another great write up, lol!!!

Troubleshooting GPR & GP's