firewall mounted electrical box

[GUNRUNNER1976]

I had something strange happened to my M 923 a2 yesterday. While starting I heard a loud pop on the firewall under hood. When I inspected I found the electrical box cover bulged out. I removed the cover and found some type of capacitor or something burnt or blown. The truck still starts fine and I can't seem to find anything not working. the box also appears to have a couple of solenoids which I assume are for the starter. Any ideas on what the heck happened and should I be worried about this since everything seems to work?...Thanks

 

[Gunnermac]

This is a protective control box, it controls all power from the batteries to the truck. There are a number of threads relating to this subject on this site including how to rebuild. Not knowing what is burned out, its hard to predict the results, but I wouldn't go far from home.

 

[Swamp Donkey]

Make sure your alternator is still charging and that the heater still works on high. Those are two of the less obvious symptoms of a bad PCB.

I'm not sure what all the insides of the PCBs do but my old one had a bad solenoid. The rest of the parts might still be good. Some folks have had success rebuilding them. Your welcome to it if you want it since your just down the road.

I'd verify that something else didn't cause the "capacitor" to blow. That might have just been a symptom of another problem. Check out the P2P program to see where everything goes and what it controls.

As Gunnermac said, don't stray far from home.

A picture inside my old box...

 

[GUNRUNNER1976]

Thanks for the generous offer. I will try to check out the internals this weekend and see what exactly happened. I will shoot you a message if i end up needing your box.

 

[GUNRUNNER1976]

looks like my blown component attaches to the top post of the top solenoid and then goes down to ground at the base of the solenoid. some type of resistor I guess