Freightliner dome light won't turn off

have you check to make sure your alone?

 

The boogeyman is real!!!!!!!!

 

Slam the doors.

 

I can help you if you are an O/O and don't afraid to mess with digital circuits. ))) FYI dome light gets the power from SAM CAB. Sam Cab gets digital signal from digital switches...Do you want the schematic diagrams ? ))

 

It sounds like Murphy has gotten into your sleeping quarters.
It might be a corroded wire in the switch(s) which is not letting the contact break. Not being sure about this, but your symptom seems like the same thing that can happen with 3-way switches in a house....you know, where you can turn off the bedroom light with a switch in the bedroom or in the bathroom... What I would do would be to pull these two switches on the dash and bunk area that you say do nothing...take a picture of them and disconnect the wires at the terminals....marking each wire and terminal....also determine which wire is the hot wire. Then, touch the hot wire to one of the two other wires to see if the cab light comes on....or not. Do it at each switch. It sounds like you have a faulty switch....which you should replace, otherwise Murphy will stick around and cause a problem later that could be costly.
BigBluePeter had a good suggestion....sometimes the door switch needs to be readjusted. A good knock will do it...but sometimes that switch gets worn and needs to be replaced or adjusted so that the contacts open when the door is closed.
If push comes to shove and you can't get the cab light to turn off....take out the bulb.

 

in the bedroom or bathroom, In the century or Columbia we don't have digitally controlled circuits.
First of all we need to understand power comes from SAM CAB because SAM CAB is #####* up or the one of two switches are sending signals to SAM CAB to power the lights. The switches are not regular switches. They have logic board in there. I would check to see if there is any active code related to SAM CAB. If there is a fault code that could indicate where to look for trouble. Next step would be unhooking one of switches and see what is happening. If in some point you have turned off lights then trouble can come from that switch. last thing would be disconnecting the wire from SAM CAB.

But if you have an DiagnosticLink or ServiceLink software you can diagnose it within 5 minute by manually activating or turning off the light from your laptop. The software would show you actual status of switches too..

Best regards

 

Everything you are syaing is true if it has a SAM CAB. But, shouldn't we verify what year/model the truck even is 1st? You're probably right, but there are still many Pre-SAM Freightliner trucks out there. Never assume.