starting to get my knickers in a knot.....

[scoutman77]

OK, I got the truck at a great deal, (so I thought). 16,500 for an '02 CC 4x4. however things are going bad fast. I knew I would have to do some work to it. New tires, new shifter (OD shut off). going to have to do ball joints before the camping season this year. However, the thing that is putting a twist in my unders is the glow plug system. The stealership said the only codes that were set were low voltage codes, hence the new batteries. (forgot that one). here is the problem. I have key voltage, I have battery power, I have voltage from the PCM, the relay refuses to trip. its new. the old relay did the same thing. should I try another? any ideas? I know I have one bad glow plug on one side and the rest are questionable but withing the test range. the other side all tested good.
Thanks
Robert-mad

 

[sagebel]

Does the truck start hard? You say you do have voltage coming into the relay correct? The glow plug signal only is sent for a max of two minutes. It is not present when the truck is running. Is the relay properly grounded? Just some ideas. Someone else will chime in I'm sure.

Scott

 

[scoutman77]

the durn thing wont start at all if not plugged in. Thought the ground would be through the bolts, cleaned the whole mounting surface with a brass brush.(didn't take off the paint) According to all I have read, the relay should be working.

 

[your2slow]

Once it's started does it run ok or seem to be lacking in power?

 

[95_stroker]

the durn thing wont start at all if not plugged in. Thought the ground would be through the bolts, cleaned the whole mounting surface with a brass brush.(didn't take off the paint) According to all I have read, the relay should be working.

Do a simple test, take one lead from a jumper cable and connect both ends to the large terminals on the GPR, leave it there for about 60 seconds or so (normal GPR cycle) and try to start it. You can also do this test wiht a heavy screwdriver if you dont get wierded out about jumping terminals with a screw driver and seeing a spark or two. If it fires up and runs like the GP's were active then you have another bad relay. What relay PN# did you use when you replaced it?

 

[scoutman77]

being as this is my first diesel, I think it runs great, I plugged it in over night, I will have to unplug it and check it this evening or tommorrow morning.
Thanks

 

[scoutman77]

seems a little knowledge helps. seems that the key provides power to one side and the pcm either provides power or ground to the other side, depending on various conditions. seems that my PCM is not setting the ground to the relay. looks like I have some work to do on the PCM. Thanks for the help!

 

[scoutman77]

fixed the glow plug issue...

its not automatic, but I can live with that as long as it starts. I took the wire from the PCM off the relay and ran to the switch which shorts to ground. thus tripping the relay.

 

[jharvey]

Not a bad idea just don't forget to turn it off!!

 

[scoutman77]

I had a momentary switch in there but didn't like it. I may yet put a push button in there.