Heater motor or Heater Matrix, what's busted this timel?

kwistof

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Hi guys,

So I left my car for just 3 days....came back and the heater blower wouldn't work last night :(

The display on the climate control dials are saying it should be blowing out air but nothing is coming out, hot or cold, with and without A/C on.

This happened last night, but this morning it actually all fired up properly....so drove to work with it blasting out some warmth.

Then once I got to work I turned the car off and on again and the heater blower went back to how it was last night and wouldn't produce any air through the vents, hot or cold.

I've checked the fuse next to the drivers door (No. 25 IIRC) and there didn't seem like any dodgy connection there and the fuse was not blown or looked faulty.

When it was working this morning there was no dodgy smell coming out- it all worked perfectly until I turned the car on and off again.

Would this be the heater motor itself as apposed to the matrix?

Any other areas I could check to determine what the fault is before I start buying parts that may not be needed- would VAG Com be able to show if the motor is dodgy? or is there any other fuses or areas to checks first as an 'easier' option?

Cheers

Chris

(2000 S3 pre-facelift)
 
When you start it off from cold Chris, the car wouldn't want to freeze you to death, so it's kind of dormant until the engine coolant/temp warms up, then it will slowly come on and warm the car as intended. Also notice the a/c won't work when the ambient temps drops below 5C, the ice symbol won't stay on, it's not broke, it's just too cold to operate the compressor in those temps!
 
Cheers for the reply Joe, however it's not blowing out any air at any given temperature...but it was this morning from a cold start :think:

I realise the air itself will not be warm until the car has warmed the coolant up- however I have no air being produced and pushed through the system what so ever.

Just popped out to the car park on my break to start her up again and there is still no air coming out of the vents with the climate control set at 'low' or 'high' with/without AC on and also various other combinations :uhm:

If I find a friendly person with VAG COM- is there any way to determine if it's the heating motor itself that has packed up?
 
You need to find the heater motor and remove the wiring connector to it. Then test for voltage at the connector. If you have voltage there then the fan is knackered, probably a dead spot on the armature of the motor.

Sometimes giving the motor a whack will fire it back into life until next time.
 
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A fan fault as in part of the heater motor or apart of something else mate?

Tbh I have no idea about this area of the car....it's the first time something in the cooling/heating area has gone wrong in nearly 5 years :\

From what I've read and seen on here the heater motor is pretty easy to replace - should take about 30 mins with a torx T25 screwdriver and located directly behind the glove box
 
If you remove the electrical connector that connects directly to the heater blower motor, usually a 2 pin plug. Turn the ignition on and put a multimeter, in DC Volt mode, on the 2 pins. Then select a fan speed and watch the multimeter. You should get a voltage showing on the screen. This voltage will increase as you increase fan speed.

If there is a voltage at the connector and it increases as you increase fan speed then that shows that the supply voltage and control circuit for the blower are working. This means the only component that you haven't tested (the blower motor itself) is highly likely to be faulty. Which, as you said, isn't that hard a job to change.

Ideally the above test should be done when the motor isn't working, which if it is as intermittent as you say can be a pain in the ring. Start with the above test and report back bud.
 

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