2005 xc70 battery/AC dead post body shop visit

ardbeglily · Post by **ardbeglily** » 01 Jul 2012, 10:09

I just want to pick the brains of the experts on the site. I needed some body work done my xc70 (replace front bumper) and when I went to pick the car up the battery was totally dead. The tech told me the guy who detailed the car must have had the doors open for a long time. My suggestion at the time was that he had the doors open, the radio and AC ON while he detailed the car. The days they had the car were extremely hot and humid in NJ. I drove the car for a few days after they recharged the battery (I did not have to use the AC) and then had to bring the car to another shop to repair the bumper properly. When I got the car back I had to use the AC and the blower fan would not turn off. On the second day the fan would still not turn off and eventually the battery died and I had to have the car towed. The battery had to be replaced as did the AC blower fan and resistor. I want to try to recoup some of the almost $1000 cost of this from the original body shop. Any thoughts or suggestions appreciated. Thank you

Post by **jimmy57** » 01 Jul 2012, 10:41

I can think of nothing the body shop could have done. The systems on the car turn off at a voltage where the car should still be able to be started and driven as a battery run down protection in the software. Leaving the key on will kill the battery but things like the climate control, radio, lighting, etc. all would have been shut down due to the low voltage long before battery got very weak leaving only the ignition coils and other fuel system things to drain the battery until it was dead.
I would think the fan stuck on while the original body shop had the car and killed the battery as a result of nothing they did.
The fan is direct wired to battery with the fan power stage (a transistor circuit, way more than a resistor) as the fan control via grounding. The failure of the fan power stage and killing battery is reported here with some regularity.
Welding or reversing jumper cable leads or other errors made with electrical system on these cars usually kills the climate control module and/or radio with no harm to fan power stage. I think the body shop's possession of the car was just coincidence with the fan motor overdrawing current and overheating and fusing the fan power stage transistor.

ardbeglily · Post by **ardbeglily** » 01 Jul 2012, 21:06

Thank you jimmy57. I wanted to get some of this clear in my head. The original body shop did such a shoddy job on the repair I had to take the car to another shop. I was just unsure of what, if anything the original shop may have done to mess the car up. Thanks again.

Post by **jimmy57** » 01 Jul 2012, 21:33

I sure would support any explanation needed to support your attempts to get your money refunded if there was culpability on their part that I could see in any reasonable way.