CaseyJay
19-07-2010, 10:32 PM
I was tweaking my CC head unit (for the non-responsive buttons - the issue with the plastic tabs breaking) as I seem to do every few months but this time when I fired it up, it was totally non-responsive, stuck on AUTO/LO and full fan.
Played around with an old unit (thought to be faulty) and same story. Tried all the buttons - only 'recirc' and 'down' show up on display. Fan meter goes up and down one notch constantly. I tried this for about 15 mins or so.
I then get the battery warning light and car fails to start. So whilst I recharge it I run VAG-COM and get the usual codes for the positioning motors (00603, 01271, 01272). Having already replaced the motor unit I don't think they are at fault.
The strange thing is the fan runs about 85% with ignition on, but when I turn on the headlamps, drops to 55% - checked this time and time again and with the battery going flat seems as if there is some kind of draw/short within the AC circuit.
Any clues where to start with this? Really concerned that running car with fan on full all the time is going to add some wear to the unit...and reluctant to buy a third used head if it's not at fault.
Cannot access the CC diagnostics as the Up button is not functioning, but have pulled measuring blocks from VAG-COM.
Played around with an old unit (thought to be faulty) and same story. Tried all the buttons - only 'recirc' and 'down' show up on display. Fan meter goes up and down one notch constantly. I tried this for about 15 mins or so.
I then get the battery warning light and car fails to start. So whilst I recharge it I run VAG-COM and get the usual codes for the positioning motors (00603, 01271, 01272). Having already replaced the motor unit I don't think they are at fault.
The strange thing is the fan runs about 85% with ignition on, but when I turn on the headlamps, drops to 55% - checked this time and time again and with the battery going flat seems as if there is some kind of draw/short within the AC circuit.
Any clues where to start with this? Really concerned that running car with fan on full all the time is going to add some wear to the unit...and reluctant to buy a third used head if it's not at fault.
Cannot access the CC diagnostics as the Up button is not functioning, but have pulled measuring blocks from VAG-COM.