2005 Freightliner Columbia DD Series 60 - Runs but wont shut off!!!

check the B piller PDM we see a lot of these get water intrusion from leaking cab seams. Pull all of the connectors out look for green residue and a burnt electrical smell. If this is the problem get it taken care of asap I have seen this problem cause cabs to catch fire.

 

I'd start with two relays, there are two power relays on right side of fuse board, like in Europe 15 and 15.R circuits relays, not sure one is marked ACC, other IGN.

 

Do you have anything aftermarket hooked on the fuse box or something like a radio? it sounds like something is feeding the ignition circuit all the time did you try unplugging the ignition switch? may be sticking.
just a thought..

 

Hi I'm also having same issue did u find the problem please help ???

 

I had the same problem there is a relay on the drivers side behind the seat on the wall. Check the relay there water can get to it then you have problems. My truck would start by its self and not turn off

 

Replace the PDM (fuse box) in "B" pillar behind driver seat. $90 from Freightliner, 1/2 hr. work. Water leaks in from window on roof. You will see corrosion in top 2 plugs when you unplug.

 

Opty-Idle?

 

Had the exact same problem, the fuse box behind the drivers seat fixed mine as well.

 

Talk about gremlins in the electrical system. That one takes the cake. What a way to wake up.

 

Hello sir thank for the reply.....we tried looked for that PDM. ...which the mechanic was familiar in the past on the Columbia. ....but mine is a classic he couldn't locate it .....I went to freightliner to find out where could be the location on mine.....but the parts guy could locate it on the computer