[GTV sean]

hi guys,

I have a strange problem on my GTV. The internal fan runs constantly at the first speed, whether the ignition is turned on or not. I removed all the fuses and relays in the internal fusebox trying to find the problem and it continues running with no fuses in place. The only way to stop it is by removing the 30amp fuse in the engine fuse box (the one to the right of the engine, above the ABS unit). This leads me to think that this fan may somehow be connected directly to the battery and possibly have a relay which may be defective. The other strange thing is that when the car is running, the fan switch has no effect on any of its speeds, as though it no longer works.

Does anybody have any understanding of how this system works. I would appreciate any input.

Kind regards

Sean

 

[spankdanny]

Like you say sounds as if the speed control has been bypassed. It take it that it has always been like this and not a new problem. I would check the wiring behind the switch.

 

[GTV-TB]

Heater fan resistor faulty, placed in the air duct near the blower.

 

[Mac gtv]

Heater fan resistor faulty, placed in the air duct near the blower.

Heater fan resistor faulty, as said before.
Watch, take note, it may get very hot, if it is faulty. It is in the passenger footwell near the fan.
Please do not burn your fingers !

 

[GTV sean]

Thanks very much guys.. This prob started not too long ago.

Where can I get such a part ? Can't seem to find one on eBay.

 

[Stixy]

Thanks very much guys.. This prob started not too long ago.

Where can I get such a part ? Can't seem to find one on eBay.

Drop an email to either Autolusso, Alfashop, Autostilo or Italia Auto Parts here in the UK. I'm sure they'll be able to help, as these garages regularly break cars.

 

[GTV-TB]

Thanks very much guys.. This prob started not too long ago.

Where can I get such a part ? Can't seem to find one on eBay.

Do a search on eBay or Google for Alfa 52466964, fitted on Alfa GTV /Spider/156/147/GT.

 

[pkr]

Be a bit careful. The speed control changed between phase 1 and phase 2/3. They're totally different. I can't tell which variant you need from your photographs.

The phase 1 speed controller is a resistor ( as noted above ) but the phase 2 controller is electronic. The phase 2 controller was also fitted to some 156s so that makes finding a spare a bit easier.

 

[GTV sean]

I forgot to note that it's a phase 2

 

[GTV-TB]

I forgot to note that it's a phase 2

52466964 phase 2 ->

 

[Henrik_45]

52466964 phase 2 ->

As PKR mentioned the Phase 2 don't use the resistor.
The control is electronic

The wiring for the control is attached.
The heater fan motor is Q1 and it is controlled by unit Q31

 

[GTV sean]

Thanks for all the advice. Can anyone please attach a photo of where I would find the speed controller? Also how do you strip the section of the dashboard that contains the air conditioner controls? There do not seem to be any screws anywhere.

Regards
Sean

 

[pkr]

Thanks for all the advice. Can anyone please attach a photo of where I would find the speed controller? Also how do you strip the section of the dashboard that contains the air conditioner controls? There do not seem to be any screws anywhere.

Regards
Sean

It's easy to find. It's located in the heater unit between the fan and the centre of the car.

Here - http://i1134.photobucket.com/albums/m615/pkr1/Samples/2011-09-26_11-22-20_DSC_001.jpg

Centre fascie - there's a 'How To' linked here -

http://www.alfaowner.com/Forum/alfa...916-spider-owners-tech-info-fault-guides.html

See post #4.

 

[wheelnut]

My newly acquired V6 24v P2 Spider has a similar problem. The 30a fuse in the engine compartment blows. No fan at all and if I disconnect the larger connector on the speed controller and replace the fuse it is fine. Do I take it that I need to replace the speed controller?

 

[GTV-TB]

My newly acquired V6 24v P2 Spider has a similar problem. The 30a fuse in the engine compartment blows. No fan at all and if I disconnect the larger connector on the speed controller and replace the fuse it is fine. Do I take it that I need to replace the speed controller?

Sounds more like a short circuit in the fan itself or in the +12V supply to the fan.

 

[Henrik_45]

My newly acquired V6 24v P2 Spider has a similar problem. The 30a fuse in the engine compartment blows. No fan at all and if I disconnect the larger connector on the speed controller and replace the fuse it is fine. Do I take it that I need to replace the speed controller?

It could be as GTV-TB mention the fan itself but it can also be a short in the speed controller.
The speed controller is a PWM (Pulse Width Modulation) device so if the MOSFETs in the controller is broken there may be a short from +12V to ground.

 

[wheelnut]

The fuse blows if the speed controller is connected, but not if the fan is connected, so I have ordered a replacement controller.
Will post the result.

 

[Henrik_45]

If you have a look on the wiring diagram (post 11) then the speed controller controls the ground side of the heater fan motor.

How did you debug the error?
Did the fuse blow in the following use case?

1. The fan is connected but Connector A on the speed controller is unplugged
   • If the fuse blows in this scenario then you have a short in the fan to ground.
   • If the fuse didn't blow when Connector A on the speed controller is unplugged but blows as soon as Connector A is connected then the fan is internally shorted between the two pins.

But after some second thought I would agree with GTV-TB that it is most likely the fan motor itself that is the problem.
Can you turn the fan motor by hand to check if it is stuck in position.

 

[GTV-TB]

A short circuit or faulty electronics in 'heater fan resistor' should give a fan that runs constantly or a fan that is not running but shouldent blow the fuse.

 

[wheelnut]

If you have a look on the wiring diagram (post 11) then the speed controller controls the ground side of the heater fan motor.

How did you debug the error?
Did the fuse blow in the following use case?

1. The fan is connected but Connector A on the speed controller is unplugged
   • If the fuse blows in this scenario then you have a short in the fan to ground.
   • If the fuse didn't blow when Connector A on the speed controller is unplugged but blows as soon as Connector A is connected then the fan is internally shorted between the two pins.

But after some second thought I would agree with GTV-TB that it is most likely the fan motor itself that is the problem.
Can you turn the fan motor by hand to check if it is stuck in position.

Thanks for the help with this. From the scenarios above, it looks as though the fan is internally shorted between the two pins.

How easy is it to get the fan motor out?
Could the supply to the fan be shorting out somewhere else? I have read of a potential issue with a wiring connector under the steering wheel.

Again, many thanks.