heater blower stopped working on 3.2

[WIL84911]

checked the engine compartment fuses and they appear to be fine. did not find haynes manual to be helpful. can i assume blower motor is shot? this is the motor directly following the heat duct from exchanger in the engine compartment correct? help please... thanks!

[WIL84911]

forgot to mention I was referring to the blower controlled by the switch above the heater levers. thanks in advance....

[porschenut]

Don't assume it's a malfunctioning blower motor, as it could also be the heater relay which sits just above the 3 fuses in the engine compartment.

Check for voltage at the blower motor connector with the heat switch on and the engine running. If no voltage, suspect the heater relay ($210 or thereabouts).

And by all means, buy the Bentley manual which is much better than Haynes and includes heater troubleshooting procedures.

[porschenut]

And take a look through this page, which contains a wealth of information on the heater system:

http://members.rennlist.com/imcarthur/911autoheat.htm

[WIL84911]

thanks very much porschenut... will definitely look into your suggestions.

[glennspiegler]

This just happened to me. Turned out to be the little air intake motor behind the dash. The fan was turning and not bringing cabin air past a sensor (round hole), due to dust. Blew it out and its worked fine since. This unit appears to control power to the system and can give your symptoms.

[WIL84911]

thanks glenn... will check that as well. was surprised when it ran once more a few minutes ago (took my kids to the park) then stopped again.

[mmauney07]

I have had intermitant blower motor operation on my 74 911 in the past and recently it has stopped. About 15 years ago, I took the blower motor apart and installed new brushes. I took some generic brushes and filed them down to fit in my motor. The soft iron brushes are very easy to shape with a file. This will probably be my next project to do again.