If the interior fan of your car runs only on highest level, it is most likely that the series resistor of the fan motor is broken.
This is a frequently occurring problem with all car brands, whether VW, BMW, Mercedes, Opel, etc. The defect is often caused by a dirty interior filter (pollen filter). A repair is usually possible within a few minutes.
Here I describe how I have exchanged the series resistor and the interior filter by my VW Touran (year of construction 2006) by myself.
Ultimately, the whole repair have cost me only about a 1/2 hour work time, 19 EUR for the resistor and 9 EUR for the interior filter.
I would like to note that I had initially asked a VW garage to exchange the resistor.
They told me that I would have to expect costs of about 250 to 300 EUR for the exchange!!!
All the more, I was very happy that I could carry out the repair by myself within a few minutes and with low costs.
PLEASE NOT! All data in the following description are without guarantee of correctness. If you are afraid to do something wrong or you are unsure, ask a qualified person to do the job!
The contents of this discription have been compiled to the best of my knowledge and belief. No liability is assumed for correctness, topicality or completeness. No liability can be assumed for damages caused by the trust in the contents of this description or its application. The instructions are only to be carried out at your own risk.
- Switch off the ignition! (Remove vehicle key!)
- Remove the “foam cover”In the passenger’s footwell below the glove compartment. Simply loose the 2 screws. Then remove the plastic cover from the center console on the left (not fixed with screws). Now, you can already see fan / blower motor.
- On the first figure you can see the cover of the interior filter (Abdeckung Innenraumfilter) and the series resistor (Vorwiderstand) of the blower motor (Gebläsemotor).
- The series resistor is located in the air stream, since it must dissipate a lot of heat power. The cover of the interior filter can be easily pushed by side. Remove the old filter and push in the new one. Slide the cover back.
- Disconnect the plug from the series resistor and pull out the series resistor by pressing the side-mounted “tab”. Install the new resistance. Check for proper seat in the air duct. Plug on it. Disassemble the panels again!
In fact, even the series resistor could be repaired, because only the fuse (Sicherung) is usually broken, see secound figure. This fuse would probably cost only a few 10 cents (!?) But, since the fuse must be welded (not soldered) due to the high temperatures occurring! I decided for safety reasons to exchange the whole series restitor.