Grounding issues possibly?

[Derek@Vision Diesel]

Okay guys... Took the cab up about 4in to give my big hands some more room to work on a stud/delete job for a customers truck.

I have fought it long enough that maybe someone has a solution.

I put the cab back down and finished hook thing things up, went to hook the batteries up and after doing so i was crawling around in the engine bay and suddenly the horn honked twice (ground issue or pinched wire was my first thought). Could not find ANYTHING that looked to be an issue.

My buddy went and opened to door and when he did that the horn went crazy, lights started flashing (cab lights and markers, no headlights). Only way to make it quit is to unplug batteries. I checked my cab to chassis ground, both battery grounds, the cab to motor ground.

Give me something else to check, cant see any pinched wires either.

 

[Derek@Vision Diesel]

The cab to chassis bolts dont ground in any way do they? I dont have them in because i can see myself having to jack the cab up a little bit here in the very very near future

 

[rentstdi]

Sounds like a security system

 

[Derek@Vision Diesel]

Sounds like a security system

Thought about that also, and it does have one....but customer says he has had batteries unplugged plenty of times with no issues.

Maybe i will dig into that and see if I can disable it

 

[cfdeng7]

Sounds like a security system

I agree

 

[Derek@Vision Diesel]

Its weird though.... the honking isnt uniform like an alarm, itll do long and short honks, sometimes even stays with the honk for 10+ seconds

 

[Derek@Vision Diesel]

I just went and checked somethings and I agree, the security system that is on the truck is probably the issue.

Just have no idea what could have caused it