HVAC and Steering wheel controls

[DNTBH8N]

I recently bought a 2003 EB, previous owner had Best Buy install a Alpine head unit. He states that after they did install, the HVAC blower motor only blew on highest setting and steering wheel controls stopped working. Before he left the parking lot he went back in and they double checked there work and said it had nothing to do with install. He didn't pursue it any further. I have replaced blower motor resistor, fan and HVAC control head, checked fuses, re-checked install on head unit. Still have same issues, anyone have any insight on what could have caused both to stop working at same time after head unit install. Thank you

 

[whtbronco]

Something certainly sounds fishy about the stereo install.

Have you scanned or codes? There are codes that can be set for the Electronic Automatic Temperature Control module, since you have an EB model I assume it has EATC. My only other thought is to start testing wires, maybe start with a close inspection under and around the radio.

For the stereo the steering wheel controls they should work if you have an interface for them and a head unit that supports steering wheel controls. For my head unit I have a Crux SWRFD-60L. It's okay, the volume up button once in a while changes the channel up, otherwise it works fine.