M1078 start issues

[Barry kvfd]

I am with a volunteer fire dept. and we have recently accquired a m1078 lmtv. I had a problem with the headlights not working and found a re-setable circuit breaker tripped. I reset the breaker and fixed the headlights. Now i have a problem with it not cranking when I hit the start button. It does not do anything at all. I have noticed that the shift panel is blank. The "N" is not lit up on the panel. Could this be the trans control module stopping it from starting? It shows a little over 24 volts on the gauge but does not click or anything when i push the start button.

 

[NDT]

Welcome. The WTEC controller has to be powered up "Lit N" in order to allow engine cranking. Take a look in the PDP (fuse box) for other breakers that are tripped or not seated well. The breaker locations are on a decal on the cover. The WTEC control has two breakers if I recall.

 

[Barry kvfd]

i checked all of the circuit breakers and all seem to be good. Earlier when I was working on the headlights, I was wiggling 1 of the 3 switches for the lights and noticed that the "n" on the shift panel would go off and come back on. I tried it again but it now stays off.

 

[NDT]

That is your problem. By switches I assume you mean breakers? Remove the one you were wiggling (associated with WTEC control) and check it with an ohmmeter. If it is defective, you can replace it with a same amp breaker from an unneeded circuit like "warning light" or "radio".

 

[NDT]

Wait, by three switches are you talking about the military light switch with 3 levers? If yes, your problem could be related to poor grounding of the WTEC keypad controller. Run a new ground wire to the controller/keypad and see if that resolves the issue.

 

[Barry kvfd]

all of the wires are white...don't know which one is ground.

 

[NDT]

Run an entirely new wire from a good ground location to one of the screws that attach the WTEC to the dash.