2013 Freightliner Cascadia

Headlights, power mirrors, power windows and instrument cluster are all getting power through the SAM CAB. Water intrusion is a known problem on SAM cab there are covers that should be in place to help keep it dry. The SAM Wall Chart found on Welcome to DTNA eComponents might be helpful. https://www.dtnaecomponents.com/Fre...DateAugust2nd2010AndNewer/SAMWallChart6_0.pdf
SAM Wall Chart shows a number of things that a logic controlled outputs and powered and circuit protected directly by the SAM CAB. Inspect SAM CAB for corrosion and/or water intrusion.

 

I am not aware of repairing SAM CAB if part of it has failed. However, proper testing needs to be done before the SAM CAB is replaced. Also, replacement SAM CAB has to be programmed to the truck. I would caution that to be sure to test for a good battery power and a good ground to SAM CAB. A couple years ago I was assigned to replace a SAM CHASSIS & program it, as it was deemed bad by diagnosing tech. Well, removed and replaced and programmed. I forgot what original problem was, but it was still there after new SAM CHASSIS installation. I then got to do some testing and found that the ground cable between the Mega Ground Junction Block and the SAM CHASSIS was bad. Replacing that short ground cable fixed the problem and it was probably 20 times cheaper than the SAM CHASSIS.