M936 wrecker electrical issue

[Polaris bryan]

I've been going through the tm's have DL many but still unsuccessful at finding a resolution to my issue.
I have a m936 wrecker and the other day I started as usual no issues , was sitting warming up as I always do. It was idling for about 15 min and the truck shut itself off.
Weird I say to myself. As I'm walking over I hear what sounded like popcorn popping then it stopped and well smoke .... @@$$$## I said ! Disconnected battery switch it all stopped. Opened hood up and found a small wire coming from starter ground to a junction point on block wrapped in loom that was quite melted.
Separated wire harness found that ground wire had melted/broke/separated itself in about 5 different spots. No other wires seem damaged that were in same loom other than slight melted spots but no bare wire showing.
After removing said ground wire truck will start , run shut itself off after 10-15 min. Try to re start the starter clicks rapidly as dead battery. I grab load tester all checks fine. Try to re start , fires right up no issue.
Volt gauge seems a little wonky low side yellow the green almost red then goes to middle of yellow. Volt meter at alternator shows 27.3 Volt running mid rpm. After the truck shut itself off again voltage shows 25.6. I scratch the head a while trying to figure it out check voltage at battery's, alternator and starter leads I get multiple readings from23.9 24 1. 24.5.
Anyone have or know where I can find a wire diagram for under the hood area??

 

[simp5782]

I've been going through the tm's have DL many but still unsuccessful at finding a resolution to my issue.
I have a m936 wrecker and the other day I started as usual no issues , was sitting warming up as I always do. It was idling for about 15 min and the truck shut itself off.
Weird I say to myself. As I'm walking over I hear what sounded like popcorn popping then it stopped and well smoke .... @@$$$## I said ! Disconnected battery switch it all stopped. Opened hood up and found a small wire coming from starter ground to a junction point on block wrapped in loom that was quite melted.
Separated wire harness found that ground wire had melted/broke/separated itself in about 5 different spots. No other wires seem damaged that were in same loom other than slight melted spots but no bare wire showing.
After removing said ground wire truck will start , run shut itself off after 10-15 min. Try to re start the starter clicks rapidly as dead battery. I grab load tester all checks fine. Try to re start , fires right up no issue.
Volt gauge seems a little wonky low side yellow the green almost red then goes to middle of yellow. Volt meter at alternator shows 27.3 Volt running mid rpm. After the truck shut itself off again voltage shows 25.6. I scratch the head a while trying to figure it out check voltage at battery's, alternator and starter leads I get multiple readings from23.9 24 1. 24.5.
Anyone have or know where I can find a wire diagram for under the hood area??

It is in the TM section under the 5ton TMs. It is a p2p program so you have to use a computer if not there are 2 threads with screenshots of the wiring diagram if you don't have computer access for the p2p program.

5-ton and up TMs

M54, M817, M123A1C, etc... the big boys! Find TM's related to the 5 ton and larger series trucks in this forum. - No posting of threads

www.steelsoldiers.com

If you bypass jump the PCB will It start fine? This is done by removing the pcb plug and jumping the 2 large pins in the plug itself on the harness side.

You may also disconnect your rear wiring harness right behind your air tube above the fuel filter canister to delete that 24v power that goes to the rear so you can isolate on the engine Harness