Do I need to flash the BCM if I replace it?
I have a 2008 Mazda 6i and the horn, brake lights and cruise control do not work. The repair shop says the BCM shows signs of water damage and needs to be replaced. Pulling the old one is easy enough and I even found a replacement on Ebay.
Do I have to take it to a dealer and get it flashed?
The BCM should not need to be reprogrammed after installation. If it does not work on power up then have it checked. It is connected to and operates many features of the car including the CAN network.
Check the old one for water damage. If it has been damaged; look at the hood release cable, these have known to bring water in to the area above the BCM and then drip water into it. A new cable is needed to repair this leak.
