Dual zone climate control issue
Any help would be much appreciated.
I have a 147 Ti with dual zone CC and have an issue with the drivers side temperature. It doesn't match that of the passenger side accordingly. If I set both zones to say 20 deg C then passenger side blows 20deg air but the drivers side will be up about 25 deg (backed up with scan tool connected and reading sensor temps). Same if i select 30 deg on passenger side and 30 deg on drivers side, the drivers side won't blow 30 deg. It's sits about 25.
Things I can confirm.
1. The right air mixture actuator works (visually seen moving and can hear it moving)
2. I have done the battery disconnect method to recalibrate CC and listened to everything setting positions.
3. The drivers side isn't stuck at a certain temp, it just has a very small range.
Things I'm unsure about.
1. The Alfa 147 climate control breakdown says there should be 4 temp sensors in the unit itself, 2x lower and 2x upper. My scan tool only shows 3 online and the 4th coincidently being the drivers centre sensor missing completely. (Greyed out on multiecu diagnostic program). I'm not sure if the temp sensor has failed or Alfa just never installed the fourth sensor in the unit. I also temporarily disconnected a temp sensor to see what it would look like and it just showed way out of scale negative number, not greying the sensor out.
I'm not sure where to go from here and if anyone could please help me out it would be much appreciated. No matter what I try, I can't get the drivers side centre vent to match the passenger side centre vent. Mono mode, or auto. Makes no difference.