Time for a new GP harness

[Lonewolf182]

Finally an update and questions.

I got one of Wes's kits for a turbo and moved the GPC. Good thing too, 2 of the wires were pressed tight to the oil fitting for the turbo and had grounded. I also had to make my own bracket for the GPC.

I decided to do a GPC bypass and followed the directions from here:
Glow Plug Controller Bypass Wiring
As Explained by Adam Clark (Diezel_Cowboy)
https://www.oilburners.net/articles/glowplugbypass.htm

Here's my question, should the "wait to start" light light up as soon as the key is turned on?
When I did a bypass on my 6.9 the light only came on while you were pressing the button.

 

[snicklas]

No... the 7.3 controller is what turns on the light. If you are bypassing by supplying a ground to the post the white wire is connect to, the WTS light won’t light. You could move the light (it is the wire with the connector in it) to the output side of the relay.... that would light the light anytime there is power to the plugs.

 

[Lonewolf182]

Thanks snicklas.

My biggest worry was that by connecting the wts light the the same terminal as the new button in the cab, you'd be making a 2nd path to ground and have constant power to the glow plugs.

So I got under the hood with a voltage tester and some jumper wire to figure things out. I also disconnected the the gp harness so that it and the gp's couldn't be hurt.

I found some strange things.
1. Grounding the control circuit didn't engage the solenoid.
2. With the key on, I was getting 7 volts to the gp harness. This was without pressing the button.
3. With the wts wire disconnected, it had full battery voltage.
4. Connecting the wts wire to ground OR a hot will turn the light on. This one's still got me scratching my head.

My best guess is that the electronic module was damaged when 2 of it's wires shorted to the oil fitting.

Anyway, I figured out a way to get the gp's working correctly. The wts wire isn't connected at all now. But I have an idea that should work and will give it a couple of useful functions.

I'll start a new thread on this alternate way to bypass the gpc when I have time to finish and test it.