heater servo not working (air con system)

[nickm321]

Hi. I have a problem with a MWB 2004 MK6 with air con, where it is permanently blowing hot. The fan was also only working on position 3. I have changed the heater resistor which has fixed the fan, but the flap servo still isn't working. I have attached a multimeter to the pins of the connector going into the servo (don't know what pins to check), and I can find the 12-14v power, but no other voltages. So am wondering if the servo might be faulty - if so where can I get one - can't seem to see them on ebay. Or if it's the electrics leading to the servo. If so, I don't really know what to look for. Could it be the heat dial?

Thanks in advance,
Nick.

[v8dave]

Have a look at this thread viewtopic.php?f=5&t=151324

When the connector pins and wiring colours are listed you need the following for a mk6

Heater control
1 - White with a violet trace
2 - White with green trace
3 - White with black trace

Actuator
3- White with green trace
4 - White with black trace
6 - White with violet trace
7 - Green with red trace
8 - Black

[nickm321]

Thanks for the info, it helped to fix the system! It turns out the actuator box was faulty. They seem a rare part, so I looked at the circuit board. There were burn marks around the chip, a 2722 op-amp. I ordered a new op-amp, and it's all working!