Alfa Romeo Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
110 Posts
Discussion Starter #1
CF3 V6 Spider

The fan is on without ignition on and cannot change the speed of the fan.

Removal of AC maxi fuse in engine bay stops it.

Any pointers please?
 

·
Premium Member
Joined
·
1,136 Posts

·
Registered
Joined
·
110 Posts
Discussion Starter #5 (Edited)
Henrik was correct.

I've replaced the part and all is well.

Thank you Henrik and you are welcome to the faulty part.

Send me your address.


It is this device you need to replace.

https://www.ebay.co.uk/itm/98-06-ALFA-ROMEO-GTV-SPIDER-916-BLOWER-FAN-SPEED-RESISTOR/333022707052?hash=item4d89b33d6c:g:i30AAOSwiMFbZQSD

If you have some electronic skills you can repair it your self.
It is normally a pair of MOSFET's that short circuit.

If you replace it I would like to have the old one. I will pay the postage if you will ship it to me.
 

·
Premium Member
Joined
·
1,136 Posts
I have received the broken part from mustbyalfa and at first it seemed not broken because I couldn't measure any shorts with my multimeter.
But then I tried to put 12V across the plug A (between A and B pin) and the a short appear and it was one of the two MOSFETs in the circuit that had this behavior.
The MOSFET only shorted at a certain voltage across it
New MOSFETs ordered so soon the unit will work again.

I will do some reverse engineering to exstract the schematic of the circuit and take some pictures of the printed board circuit for anyone to repair it in the future. Stay tuned :)
 

·
Registered
Joined
·
110 Posts
Discussion Starter #7
I have received the broken part from mustbyalfa and at first it seemed not broken because I couldn't measure any shorts with my multimeter.
But then I tried to put 12V across the plug A (between A and B pin) and the a short appear and it was one of the two MOSFETs in the circuit that had this behavior.
The MOSFET only shorted at a certain voltage across it
New MOSFETs ordered so soon the unit will work again.

I will do some reverse engineering to exstract the schematic of the circuit and take some pictures of the printed board circuit for anyone to repair it in the future. Stay tuned :)
Good man Henrik
 

·
Premium Member
Joined
·
1,136 Posts
Got the MOSFETs today and repaired the unit.

In case others would like to repair a faulty unit I have made this guide

  1. Remove the black plastic enclosure at the end of the unit.
  2. Grind of the two small rivets (use a suitable grinder)
  3. Remove the braket that holds the two transistors (MOSFETs) and remove the PCB.
  4. Unsolder the broken MOSFETs
  5. Drill holes for screws where the rivets were (I used 3.2mm screws and drilled a 3mm hole)
  6. Mount the new MOSFETs, bent the pins of the MOSFET in a 90° angle, place the PCB on the aluminium cooling plate and place the MOSFETs
  7. Solder 1 pin in order to get the right distance, remove the PCB and solder the rest of the pins.
  8. Place the PCB back on the cooling plate and mount the bracket with two screws
  9. Done.
I have attached some photos as support for the guide.
 

Attachments

1 - 11 of 11 Posts
Top