Heater at Full Power

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Heater at Full Power

Post by ostreet » Mon Oct 03, 2005 2:13 pm

The Heater Blower runs constantly at full power even when the dial is turned fully to off. The Dial is working, spent a day crawling aroud inside the dash to confirm that. Also when turned to off the air is blocked from entering the car. Fan still runs at full power.

Any thoughts.


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ken newbold
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Post by ken newbold » Mon Oct 03, 2005 3:00 pm

Hello and welcome aboard.
Sounds like your heater blower module has failed. You'll find this located in the blower duct just downstream from the motor.
You will need to remove the skuttle from under the windscreen and undo the 3 (i think) 10mm bolts/nuts and 1 pozi screw securing the duct. Once you've managed to turn the duct on to its side you'll see the module with plug and about 4 wires.
New ones are about £20 but you may be able to get one via local scrappies.
Good luck. Ken
They think it's all over, it is now!

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Post by tom » Mon Oct 03, 2005 6:11 pm

Either the transistor has failed collector-emitter short: most unlikely or the full speed relay has welded its contacts together which is more likely. I'd begin by disconnecting the full speed relay which is beside the steering column. If you still have the fault, there will need to be some sleuthing done. I have never yet failed to sort one of these out but If you can wait until ground control puts up the new Ramblings column, which won't be long there is a detailed guide to sorting out faults which you will find helpful, at least to rule out various possibilities.

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Post by ostreet » Tue Oct 04, 2005 10:57 am

Cheers for the suggestions guys.
Will have a root around and see if I can find the high speed fan relay. And if that doesn't work i'll take the Heater blower module route. (and be back when I realise I don't quite know what i'm doing :D )