Electrical Issues 2004 V70

[dout919]

Hello, I recently joined the club with a 2004 v70. Drove great for a few weeks but then started showing electrical issues. Headlights clicking on and off, transmission shifting poorly, gauges turning on and off, and the engine was throwing the following codes: ECM-801A
CEM-1A59
CEM-8F43
CEM-1D08
CEM-1A61
CEM-1A62
I saw posts on here from people with similar problems, and people said changing the CEM and TCM modules fixed this issue. I just changed the two modules and the same codes are still coming up, and now the engine will crank but won’t start, and in addition to the old codes, the following new codes have shown up: CEM-E000, DDM-003B, DDM-003C, and DEM-000A. Everything on the car is stock with the exception of an aftermarket stereo I put in. Has anyone had a similar issue or can anyone point me in the direction of what I should look for? Thank you if anyone can help me with this.

[jonesg]

did you disconnect the battery when installing the radio ?

Spill any sugary drinks on the console lately ?

[dout919]

I did make the mistake of leaving the battery connected during the radio install. It gave me an airbag code, I took it to a Volvo tech and he cleared it for free but warned me that there were a plethora of other electrical codes coming up, but he cleared them without telling me what they were. It drove completely fine for weeks after that but I have been fearing that I shorted something when I did that.

[jonesg]

i took care of my DEM code by pulling the fuse, you will get a different code doing this.
I would also try disconnecting the new radio, see if that is causing throughput problems.

a working version of vida and a dice unit would help solve this, at least find circuit diagrams and start checking powers and grounds.