No crank after dash removal

[Russ Hersh]

So got a M1078A1, swapped batteries out and got it running, i removed the dash to paint it and to clean up the gauges, i marked most of the connectors to where they correspond, and now i can not get the truck to crank, the button does nothing no relays click, and when i turn my park and headlights on, it trips the relay for the main switch, Ive searched the forums for something similar but i have a large feeling i maybe mislabeled a connector or this random black wire with a ring terminal inside he dash goes some specific place. The CTIS module is off the truck for the time being but i doubt that would be giving me the issue, am following TM trouble shooting and everything is saying to replace dash wire assembly, any help is greatly appreciated!!

 

[wheelspinner]

Go back under the dash-make sure
Plugs (912 and 913 I believe are the numbers) are not plugged together. They look like they should be but are option cables for dump and van bodies

 

[Russ Hersh]

Go back under the dash-make sure
Plugs (912 and 913 I believe are the numbers) are not plugged together. They look like they should be but are option cables for dump and van bodies

i checked 912 and 913 are not connected and they are not, i went ahead and disconnected the main light switch and my no start issue is still present, im gonna use the tm to look through what connect goes wear to make sure im good there

 

[Russ Hersh]

checked connections and yes had a few swapped, corrected that and also tested start inhibit relay and relay checks out good, so something is causing that to not allow cranking, also my main light switch is still tripping its resettable fuse

 

[Ronmar]

What comes on/goes click and what dash lights illuminate when you turn on the main sw?

 

[Russ Hersh]

What comes on/goes click and what dash lights illuminate when you turn on the main sw?

all the standard lights come on from the indicator panel, i did some more troubleshooting from the TM after noticing the gauges wouldnt move on start up so i checked that fuse, lo and behold that fuse was bad so i place a regular automotive fuse same amp rating and buzzer came on, gauges moved and started up, i believe it was cb 77

also my main light switch is still acting up, has proper voltage but when you wiggle it, it resets, pins on both ends looked good so might be a ground issue, wires at the connector looked good too.

 

[coachgeo]

all the standard lights come on from the indicator panel, i did some more troubleshooting from the TM after noticing the gauges wouldnt move on start up so i checked that fuse, lo and behold that fuse was bad so i place a regular automotive fuse same amp rating and buzzer came on, gauges moved and started up, i believe it was cb 77

also my main light switch is still acting up, has proper voltage but when you wiggle it, it resets, pins on both ends looked good so might be a ground issue, wires at the connector looked good too.

Some early A1's if I recall right had issues with the light switch that was the upgrade from the A0 version. It had no ground wire. It was planned it would ground proper thru the bolts...and it didn't work out that way in reality. CARC is beasty lol.....

Anyway after a few fires and other issues they moved again to another A1 light switch (outside looks same) but has a lug on back for a ground wire..... and it got a ground wire run directly off of it to a ground spot nearby. Soooo if you "do not" have that newer style with a ground lug... and you painted the cover.... then yeah.... I bet you have ground issues. Not sure where to put and run a wire from the non lugged light switch to a ground though.

 

[Mullaney]

all the standard lights come on from the indicator panel, i did some more troubleshooting from the TM after noticing the gauges wouldnt move on start up so i checked that fuse, lo and behold that fuse was bad so i place a regular automotive fuse same amp rating and buzzer came on, gauges moved and started up, i believe it was cb 77

also my main light switch is still acting up, has proper voltage but when you wiggle it, it resets, pins on both ends looked good so might be a ground issue, wires at the connector looked good too.

.
It is a sucky job, but spending a couple of days sitting there in the Co-Driver's (passenger) seat of your truck - with the batteries disconnected - cleaning the contacts would improve your truck in a big way. Using Anti-oxident paste and/or anti-ox spray or contact cleaner and then paste just needs to be done.

These trucks are driven by eighteen year old young'uns that didn't pay for them. It rains and the window is down, your personal vehicle and you run out there and roll up those windows. In the military, a motor sergeant will rip you a new one for not taking care of his (her?) equipment but really - they don't care unless it is their butt sitting on a wet seat. Sand and Dust blown in those same open windows settle into the contacts too.

 

[Russ Hersh]

.
It is a sucky job, but spending a couple of days sitting there in the Co-Driver's (passenger) seat of your truck - with the batteries disconnected - cleaning the contacts would improve your truck in a big way. Using Anti-oxident paste and/or anti-ox spray or contact cleaner and then paste just needs to be done.

These trucks are driven by eighteen year old young'uns that didn't pay for them. It rains and the window is down, your personal vehicle and you run out there and roll up those windows. In the military, a motor sergeant will rip you a new one for not taking care of his (her?) equipment but really - they don't care unless it is their butt sitting on a wet seat. Sand and Dust blown in those same open windows settle into the contacts too.

Fun fact i drove these as an 88m, in the reserves so ive seen the exact same things being mentioned but at the same time i learned how to take care of the equipment that ive had to drive and to help maintenance out when possible because in the worst case scenario i always wanted to know how to make it back if my life depended on it. This truck is for my fire department and they picked up 2 so ill swing over to the other one and see where the stand alone ground is. Thank you for that bit of info it really helps out!!

 

[Russ Hersh]

final solution to issue was poor grounding through panel, i ended up sanding a few of the threaded inserts and the backside of the panel in same location and everything works as it should, thank you guys for the help and insight!!