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Hello there,

My heater blower has suddenly decided to stop working. As all the lights on the climate control panel still come on and you can hear actuators moving when selected and no fuses were blown I assumed it must be the fan itself.

 

I checked that there was voltage at the motor connection with the fan selected on and I got the corresponding correct voltages ( 4, 6, 9, 12). So assuming it was the motor I took it out and tried cleaning it using the info on here. No joy.... So I sourced a replacement fan, fitted it... still no joy.

 

Reading through my workshop manual I found the self diagnosis test for climate control so tried this. Upon starting the test I didn't get the '00' code which says duff Auto/Off switch. So accordingly I have sourced another one although it is slightly different appearance it had the same connections. I put it on and did the self diagnosis test again, still no '00' code at the start.

 

Any ideas please...:headvswal

Featured Replies

Where did you measure the voltage?

 

Between the motor terminals or between one motor terminal and earth?

 

If it was the latter, you have a crook earth.

  • Author

I should point out that I'm no electrician.....

 

I put my volmeter across the two spade connections inside the white plastic plug that is part of the loom where it connects directly to the motor.

  • Author

Is the speed module on the housing that the fan motor bolts into? I'm suspicious about two fans being dead, but you never know....:confused:

I'm suspicious about two fans being dead

Me too but if you have measured the voltage as you say, at the motor terminals, there is nothing elase left. Are you sure you are on the motor terminals?

I have the same problem, but im lazy and havnt investigated at all, shamefull really as im a mechanic... After reading this thread I think nzniggles was right the first time, re check your earth.

Better still, get a length of wire and create a new earth altogether and supply that directly to said fan motor.

  • Author
Me too but if you have measured the voltage as you say, at the motor terminals, there is nothing elase left. Are you sure you are on the motor terminals?

 

Yes I'm certain I'm on the motor terminals. If there was a duff earth or even a short there, would it still be possible to measure a voltage at the terminals? :confused:

If there was a duff earth or even a short there, would it still be possible to measure a voltage at the terminals?

If you had a crook earth and measured across the motor, you wouldn't have a voltage. You'd only get a voltage if you measured between the motor and earth.

If you measure across the motor and didn't get a voltage, then it is a supply or earth problem (this can included the resistor pack).

If you measure across the motor and get a voltage then it must be crook motor (open circuit).

How much current does the motor pull? If it's a duff but slightly connected earth, wouldn't the meter still read the voltage, but under load the connection wouldn't suffice??? Never had this problem, but still thought I throw my two-pence worth in :-)

If there was a duff connection bad enough to stop the motor running, there wouldn't be a voltage (or a very low one).

  • Author
How much current does the motor pull? If it's a duff but slightly connected earth, wouldn't the meter still read the voltage, but under load the connection wouldn't suffice??? Never had this problem, but still thought I throw my two-pence worth in :-)

 

Funny but I thought something along those lines too, but as I said I'm no electrician. I much prefer fuel or hydraulic systems, at least you can see/smell when it's leaking.... :rolleyes:

I much prefer fuel or hydraulic systems, at least you can see/smell when it's leaking....

You can see where wires are leaking too ...... the hard bit is putting all that smoke back into them ;)

  • Author

Sorry to harp on but... I finally decided to actually check the fan(s) by running wires to them straight from a battery and funny old thing they both work..

 

Have also as the manual suggested tried changing the whole aircon control switch pod as per the workshop manual recommendation, although this would appear to be a slightly older version.

 

There's still no '00' when you put it into self diagnostic mode so could this be due to the switch unit being slightly different or as has previously been suggested a dodgy earth and/or connection somewhere? I have started to occaisionally hear a clicking noise from behind the dash, but it's only ever at idle and not all the time either. :headvswal

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