No WTS, No start...

[coinball]

The SES light is lit when the key is in the ON position, all other lights work as normal - minus the WTS light. The truck will crank all day, but not fire off. If I crank long enough I will get white smoke out of the exhaust. I know the glows are indeed running since I can test them with my manual controller. I don't think the ECM is getting power because I cannot connect to it with my GMTDscan tool, but I'm confused as to why the SES is still lit...

Any ideas?

[DmaxMaverick]

It's normal for the SES to be on with the key on, and the engine not running.

No WTS, no GP heat. That's why is won't start. The WTS lamp is powered by the same voltage sent to the GP's. White smoke = fuel, but too little heat (no GP's). Depending on how your manual glow is set up, your switch is doing the same as the controller, if you power it and still not start. I'd suspect the relay or fusible link.

[coinball]

I can hear the relay click on and off whenever my manual GP switch is on, but the light on the dash does not light up (it is wired to light up the dash when on, wired by previous owner).

It also cycles when the key is turned to ON, but still no light on the dash.

I didn't have time to check the voltage at the GP relay before coming into work, but I'll dig into it this afternoon.

[coinball]

1. The GP relay is dead.

2. The 10A Glow plug fuse under the hood is not getting any power. I don't have any wiring diagrams so I can't tell if there is a fusible link somewhere in that circuit. However if I bypass the 10A fuse and take a wire from the battery to the fuse spade the WTS light will illuminate.

3. There is one orange wire giving 12V to the ECM, but no others (orange anyway, again I have no wiring diagrams, so I don't know what other wires to check. I still cannot connect my gmtdscan to the ECM...

[rhsub]

Eric
Here is what I can figure out from my manuals
wiring at relay
red - Bat+ fusable link in circuit (main power to relay)
yellow- PCM glow plug relay control terminal C13 at pcm (turns on relay by grounding it)
black- ground
pink/black- guages fuse (powers switch side of relay)

orange- connects to left bank glow plug harness, to gp fuse to PCM (glow plug signal terminal B8) and wts light, all glow plug fuse operates is light and signal to pcm

hope this helps
Ron