Could the software updates that cause all these new codes be a sign that the CEM (central electronic module) is starting to go bad?
What brings me here this evening is the 2001 V70 XC. I always deal with a small Volvo (only) garage for all work – but they sent me to a local dealer to get ECM/TCM programming software updates, because they don’t have that equipment in-house. The car had occasional transmission hiccups, and they’d seen bulletins about updates that could address that.
Anyway – when the dealer hooked up the car to their equipment to check the code versions, etc, and ran a diagnostic, it came back with all sorts of “DTC is found active/not active” status errors on about (14) different things. The service guy pointed them out to me. What he was showing me was that he was seeing no transmission codes, but many other unrelated ones. These included the door control module (driver), many other door-related signal alerts, sunroof error, etc.
He asked me if I’d had problems with any of these things and I answered (truthfully) no. Up to the point I parked at the dealer, all door switches, etc, were working fine. I told him that, despite what the codes might be showing, none of the problems were manifesting, so I had no interest in replacing anything based on codes.
Problem is, after they updated ECM/TCM software and buttoned it back up, NOW many of these codes are manifesting. The driver’s door controls are all completely inoperative. The bush-button lights up top don’t work. The sunroof controls are dead.
“A used DDM (drivers door module) will not work for you, once software is installed on any module, it cannot be used on any other car. Not sure why they would sell you one, they should know better. The best analogy I can think of is when you burn your own cd’s. Once you burn songs onto a blank cd, you can’t remove the old songs and burn new ones onto the disc. It’s a one time deal. Very similar setup with Volvo modules, once they have been installed or used on a car, they are only able to be used on that particular car, they cannot be re-sold and used on another car. That software is “burned” onto the module, and it can’t be removed.”