Hi,
I've got a set of electrical issues I'm having a hard time resolving in a 1998 K3500. Any ideas are much appreciated. Here's what happens:
-- truck usually starts and runs great. About one time in 10, though, the glow plug light goes out right away and no matter what it won't start, it cranks, but doesn't catch. When this happens smoke also comes out of the turbo when I try. Hooking a code reader up to the truck results in a "glow plug heater circuit" code.
-- I can usually get it to start by wiggling the wires around the glow plug controller, indicating to me that something is loose in there. I've taken everything off and put it back together a couple times, though, and the problem keeps coming back.
-- several times now, the truck has mysteriously died. In each case right after going over some bumpy roads or steep hills, the same glow plug heater circuit code appears, so I presume it is the same electrical issue
-- after the last time, I also got an ABS code for "Brake switch A". The strange thing about this code is that it doesn't show up in carcode in a way that lets me clear it (usually on the enhanced page of carcode I get several servers responding and then can clear the codes they are bringing up, but the ABS server never responds.)
So, specific questions:
-- is there something internal to the glow plug controller that could be causing a problem like this? Which connection on the controller is most likely to correspond to the heater circuit? It would be the white plastic connector from the harness, not either of the bolt down connections, right?
-- where should I start looking for "brake switch A"? I presume that this is an unrelated problem since it just started happening after I went over some pretty bumpy roads, even though it appeared during one of the mysterious dying incidents.
Thanks for your help!
--Derek