M1079 electrical help please.

[K10A]

Hi Everyone, I am heading to go try and help a fella get his m1079? Box type truck running. He states he has new batteries and some small wires for start interlock were rodent chewed but repaired. Still has a no start condition. Some electrical works and some doesn’t. He has been living in the box as a camper and I think all that electrical works but they are now selling the property and need to get the truck running to relocate and sell the truck. I downloaded the electrical schematics. He says he has a big manual for it but he is not good with electrical. . Any suggestions are appreciated ! Thanks in advance.

 

[Ronmar]

well it helps to know the year/model? is it an A0 or an A1?

With no crank, The first thing I always look for are what relays energize when the ignition is turned on, and what relays energize when the button is pushed.

With ignition on K11 and k24 i think should energize, along with the low oil idiot light in the dash. k11 and k24 are controlled by the same 15PSI low oil switch that controls that idiot light. The light and those relays being energized enables the start circuit.

When you push the button the start relay in the dash should energize. That relay in turn energizes the large current aux start relay down on the drivers frame rail near the power steering reservoir. the aux start relay energizes the starter solenoid on top of the starter to crank the engine...

If it is an A0 i can get you a simplified start circuit diagram later when I get home...