M931a1 electric issues

[USN_Green_Addict]

A friend of mine has a M931a1 that no electronics work at all, no lights, no click trying to start, nothing. He last drove it a month ago. He just installed 4 new batteries. I've been searching for circuit breaker or fuses for it but I can't find anything. I've worked on M35A2 but not any 5 tons.

 

[simp5782]

Smack the black pcb box behind the washer bottle with a Hammer.

 

[Jbulach]

Looks like the batteries are wired wrong.