Trouble code p0863 TCM

[XmenXc90]

Hi am new to the site and was searching for the same symptoms with my 2004 xc90 throwing same code. Glad to hear like you've got the issue resolved finally. I did find info about a known issue with the CEM for newer years that was related to water intrusion on CEM and low heat resistence for 2004. My dash goes out as well as windows and ac and i get what seems like a tranny thump and car goes in limp mode.

Does xemodex troubleshoot the CEM once received to confirm it is faulty? I may have to go this route.

[abscate]

Nice, I wonder what they do to address heat issue? Your work above was top shelf so I’m guessing the problem was off the CPU somewhere.

I believe the 2005- CEM does not suffer from heat stroke.

[22volvo]

We had no water intrusion on the driver's side (still have it on the passenger's side) so our CEM issue was strictly heat related. xemodex in canada did do a prelim test and confirmed the info we sent them. If you can force it to fail with a heat gun (hair dryer) and make it work with freeze spray (keyboard duster used upside down), then you have some chips in the CEM that are failing with heat stress. Heat sinks will keep it cooler but if it's parked outside in Texas on a 100 degree day those chips are already in failure mode when you start it up.
We've had no problems since the unit repaired/returned from xemodex.