Help! Electrical Gremlin in the glow plugs!

[Tesla]

Just got my truck (89 Suburban 6.2L V1500) back from the transmission shop with the freshly rebuilt 700R4 in it. Yay working transmission!

So, of course, another problem had to immediately pop up. First is that whenever the instrument panel lights are on, the "sounder" (I call it an annoying buzzer) goes off continuously. Second, and more importantly, my glow plugs don't work correctly anymore.

I found a wiring diagram of my glow plug electrical system that I'm going to try to attach to this post to help explain things.

After lots of poking around under the hood with jumpers and a volt meter, what I eventually figured out is: I'm not getting any voltage on the Terminal "D" on my glow plug controller. The wiring diagram indicates that this Terminal is fed from the ignition switch.

When I jumpered 12 volts straight from the battery to Terminal "D," the glow plug light came on in the cab and the truck started up and ran great.

So, any ideas about why I'm not getting power from the ignition switch? Is it related to the sudden never-ceasing buzzer? I need some help on what I should test next.

 

[tRustyK5]

It's probably not a coincidence that you just got it back from the tranny shop and now you have a weird issue. Double check the ground strap got bolted back to the engine. Also, double check that no wiring got between the engine and the bellhousing when it got put back together. crushing a wire there has been done often and leads to interesting problems depending on what wire got pinched.

Does the '85 up system use a solenoid on the fenderwell like the earlier systems did?

Rene

 

[Tesla]

Yeah, I was thinking the same thing. I mean, the transmission guy had to be the culprit. So after a couple of hours of running down and testing wires everywhere, I finally found the culprit...

A burnt out fuse! Yep, I'm an idiot. Always check the easy stuff first!

Everything is working fine now.

 

[tRustyK5]

Well, just blame the blown fuse on the tranny guy...that'll make you feel better.

Glad it was something simple!

Rene