Truck shuts down when I turn on my lights switch

I have a 1995 freightliner fld120 with a DDs60 and no matter if I’m driving or if I’m sitting still the truck will emergency shutdown when I turn on my lights. Barely started happening Monday and I took a week off before that. Both the check engine and emergency shutdown lights cmon on. When I drive all day without the lights on it runs perfectly fine but a minute or so after I turn the lights on it shuts down. I have no clue if this is simple or serious.

 

Some one has been making changes in wires behind the dash??

 

My only guess is that your light circuit is somehow tied into/rubbed into a low oil pressure switch or other critical shutdown event.

If it has a diagnostic switch you can toggle that and read the 'blink codes' - better yet have it plugged in to see what the CEL/SEL codes were.

It may help you isolate the problem.

Report back please !

 

No the truck sat for a week while I was at home.

 

Where would I take it to get the codes scanned? The dealer? I don’t have a scan tool

 

Dealer sure, but any heavy diesel mechanic should have one that works with an engine that old. Call around and give the symptoms and see id they can diagnose it.

Sounds like a bad ground somewhere, or a broken wire that is causing feedback when you turn the lights on. Don't expect it to be found right away, but on the same token the mechanic might get lucky too.

 

I got the above pictures looking at the trucks relays and stuff and a bolt was broken securing a line coming from the batteries. Could that be it? And what’s the pats name that holds all those cables together?

 

Go to your FL dealership with the VIN and that picture, I’m guessing you’ll need that whole block, unless those bolts are replaceable from the rear side.

 

Yea I’m trying to get home this weekend to fix this I’ll see if it’s the problem . Thank you guys.