Ok, i used a voltmeter to check relayfrom battery. Got 12 volts on one side and nothing on the other of relay, with key switch on and off... Is this the correct way to check it? If so, i guess i have a bad realy?
Thanks

 

That is it.. But i think it is temperature related. It has to be cold out. Not sure what the temperature cut off is.. 50f?

 

Do you get the "wait to start" light? The relay will only have battery of both large lugs when lamp is on.

 

Not true... the relay stays engergized much longer than the WTS light.

 

The GPR also may not be required to come on, even if the wait to start light is on..

 

I think it is based on the outside temp. If it is hot out (above a certain degrees oil temp above 70 ???) the PCM won't tell the relay to latch. Correct me if i am wrong but i don't think it activates on warm/hot days. I don't remember what the activating temperature was. But i always get the "wait to start" light reguardless of temp.

 

I agree with Dan, on a 90* day, my wait to start is on, but GPR LED is not.

 

Here you go. Actual glow plug on time vs. the Wait To Start lamp.

 

That seems higher of temp then when i messed with it last year. I don't remember it being that high. I messed with it last year and don't remember all the temperatures vs GPR time. I think mine behaved like Pats did. 90 degree, mine didn't activate either. I didn't have the AE back then but i shot the oil pan with my Laser Temp thingy.


What is states out of my Manual.

The glow plug system is electronically controlled by the PCM. If the temperature is below 55°C (131°F) the PCM will energize the glow plugs immediately after the key is placed in the ON position. Then, depending on the readings from the engine oil temperature (EOT) sensor and the barometric pressure (BARO) sensor, the PCM detdermines how long the glow plugs will be on.

Glow Plugs — PCM-Controlled

The glow plugs are located in the cylinder heads (6049), under the valve covers (6582).

The glow plugs are self-regulating. If the engine oil temperature is above 55°C (131°F), the PCM will bulb-check the WAIT TO START lamp but not energize the glow plug relay or control module.

The PCM system uses the glow plug module (if equipped) to conduct current to the left and right bank glow plugs.

The PCM protects the glow plugs by energizing them for short durations if the battery voltage is abnormally high.

The glow plug ON time varies from 0-120 seconds depending on battery voltage, engine oil temperature and barometric pressure.

On California vehicles the glow plug monitor (GPM) system is part of the On-Board Diagnostics II (OBD II) System.

The GPM system is designed to find failed glow plugs or failed wiring in the glow plug system.

A failure in the glow plug system will set a diagnostic trouble code (DTC).

 

55 degrees C IS 131 degrees F

Oops disregard that comment....it says that in what you posted, Dan.

I don't make the rules, I just post what I have.