Fuse 6 Blows
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From: CT
Fuse 6 Blows
As I stated elsewhere, in my 1989 S4 the blower fan stopped working. I found Fuse 6 (AC) to have blown. Replace it last night and the fan and AC were working once again. This morning I start the car, and the fan/ac no longer work and the fuse is blown. By the way, the ac and fan were not on when I started the car.
As a side note, the interior temperture sensor fan had been making quite a bit of noise recently and then the noice suddenly ceased--I do not hear the sensor fan spin either at this point.
Question, if the fan is shorted for some reason, is it connected to this particular fuse?
Any leads on how I go about testing for this blown fuse?
Thanks.
As a side note, the interior temperture sensor fan had been making quite a bit of noise recently and then the noice suddenly ceased--I do not hear the sensor fan spin either at this point.
Question, if the fan is shorted for some reason, is it connected to this particular fuse?
Any leads on how I go about testing for this blown fuse?
Thanks.
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From: Phoenix AZ
Fuse 6 feeds the HVAC head unit - seems likely you have an issue in the control switch or the control unit - that would also potentially affect the internal temp sensor & fan (or that could still be the issue too) You shouldn't really be able to hear the sensor fan anyway - so seems it was very noisy?
Fan is driven via the control switch...
Debug is somewhat complex here....
First did everything work last time before the fuse blew?
Next get a bunch of 7.5A fuses....
Do any of the following either not work correcty or individually cause the fuse to blow consistently:
AC switch
Fan switch (all positions work correctly?)
All heating/cooling director switch positions inc Defrost Setting?
Limit switches either way Max & Min temp settings
You may want to unplug the temp sensor fan and test it....
Alan
Fan is driven via the control switch...
Debug is somewhat complex here....
First did everything work last time before the fuse blew?
Next get a bunch of 7.5A fuses....
Do any of the following either not work correcty or individually cause the fuse to blow consistently:
AC switch
Fan switch (all positions work correctly?)
All heating/cooling director switch positions inc Defrost Setting?
Limit switches either way Max & Min temp settings
You may want to unplug the temp sensor fan and test it....
Alan
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Joined: Jan 2002
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From: CT
Thanks, Alan.
I'll need to get some more fuses for more testing as you suggest. But when I first replaced the fuse, I tested the fan in all positions (all worked) and then tested the AC which worked as well. I let it run for a bit, and switched it all off. This morning, start the car--no ac, no fan--blown fuse.
Do I access the temp sensor fan by removing the HVAC head unit.? Nichols site said to replace the sensor fan, the dash needs to come out.
David
I'll need to get some more fuses for more testing as you suggest. But when I first replaced the fuse, I tested the fan in all positions (all worked) and then tested the AC which worked as well. I let it run for a bit, and switched it all off. This morning, start the car--no ac, no fan--blown fuse.
Do I access the temp sensor fan by removing the HVAC head unit.? Nichols site said to replace the sensor fan, the dash needs to come out.
David
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From: Phoenix AZ
David,
I don't know on removal - I gather its hard and you have to release the sensor cover from the underside of console (as in remove it)... others?
However the connector for this is in the console near the AC head unit - you may only need to access that.... certainly to test it...
4 pin connector T31 - 2 x yellow wires for the temp sensor and a Red/White & Brown for the motor
+ goes to to the Red/white & Gnd to the Brown - see if it works correctly. Obviously it should run ~silently and should draw (I'm guessing) <<1A - its just a very very small fan.
Alan
I don't know on removal - I gather its hard and you have to release the sensor cover from the underside of console (as in remove it)... others?
However the connector for this is in the console near the AC head unit - you may only need to access that.... certainly to test it...
4 pin connector T31 - 2 x yellow wires for the temp sensor and a Red/White & Brown for the motor
+ goes to to the Red/white & Gnd to the Brown - see if it works correctly. Obviously it should run ~silently and should draw (I'm guessing) <<1A - its just a very very small fan.
Alan
