Glow plug wiring question need help

[AKTikki]

I have a 1998 GMC Sierra 2500 that I'm putting back together. When I put the motor in I noticed that the glow plug wiring was missing on this. I yanked the wiring out of my 94 and can't find where the fifth wire on the driver side set of glow plugs connects into the system. From the wiring diagrams I see that the orange wire goes into a dark blue wire I can't find that anywhere though. If someone who owns in 97 and above could take a picture under the hood where that wire ties into the system I would really appreciate it as it would eliminate trying to search through the entire wire loom.

 

[Jaryd]

Hopefully this helps. If it's not what your looking for let me know. Ill try to take more pictures. My truck is a 2000

 

[AKTikki]

View attachment 50513 View attachment 50514 Hopefully this helps. If it's not what your looking for let me know. Ill try to take more pictures. My truck is a 2000

It does point me in the right direction at least i know I'm looking for a brown wire now I just need to figure out where that one goes mine doesn't exist. Is that part of the engine harness or part of the wiring going into the firewall? My engine harness is from a 94 as well so I might have to Fab up something just to make the connection

 

[Jaryd]

It's going in the biggest harness plug at the back of the firewall. I guess the best way for you to do it would be to look at the plug and find the red, grey and green wire that are beside each other on the top left with the plug rotated this way. The wire your looking for goes on the top row and to the far left.

 

[Paveltolz]

Here's an annotated schematic from a 97 manual (splices and distances). Hope it helps

 

[AKTikki]

Thank you so much guys. Found the wire and got it fixed. That was driving me crazy! All good and check engine light is off (thank God)

 

[Jaryd]

I'm Glad you got it straightened out