Interior heater fan not working

thanks for the reply. Now I do not have time to watch tonight but you know.
Thank you so much in the meantime

C3driver52 wrote: The fan is supplied with 12v from the engine bay fuse box. It is switched on by grounding pin A4 on the control panel connector (according to the diagrams I have here).

A4 can be seen marked on the socket, its very small writing, but look for the black wire, then double check; Row A, Column 4

Ground A4 should get the fan to spin if the engine bay fuse box is supplying its 12v.
(it will need the computer signal to get the BSM - engine bay fuse box relay activated, switch the ignition on)

Post some pictures of the plug because I do not see where it says "A4"
the last picture you can see that there are 2 cables blacks that you can see in my sketch
the pins one and two I found them under the steering wheel near the accelerator
tomorrow I double check all the fuses again
But is it right that I do not have the 12V in those two wires with the machine turned on?
What would be the A4 pin?
And where should I connect it?

Post some pictures of the plug because I do not see where it says "A4"

Its on the side with the wires (the only bit you didn't take a picture of). You will see A1 B1 A and B.

Its difficult to tell from a photo, but the connection with the arrow looks a little burned, worth investigating


Have you seen this post? (here) it shows melted and burned bits on the heater control panel. You may have something similar if its a common fault.

But is it right that I do not have the 12V in those two wires with the machine turned on?

That sounds ok, but I will have to check tomorrow.

What would be the A4 pin?

Its the other side of the motor, the side that needs to be grounded or earthed to get the current flowing.

And where should I connect it?

Earth. (Ground), battery negative.

the last picture you can see that there are 2 cables blacks that you can see in my sketch

The Haynes Manual (here) has some very useful wiring diagrams and shows the heater control panel wiring in detail.

the pins one and two I found them under the steering wheel near the accelerator

There are often plugs and sockets unused on a particular model, even the exclusive has some spare plugs that are unused.


Look to see if that plug is burned and look at the control panel socket (open it up) and see if that is melted or burned...

C3driver52 wrote:

Look to see if that plug is burned and look at the control panel socket (open it up) and see if that is melted or burned...

Yes, I looked in control panel and there are some parts a little melted. Even the pin 1 and 2 of my photos are, if you look a little burnt. But in order to understand if it is the control panel that is broken before I have to run the fan without control panel finding this blessed "A4" and linking it to the ground. If the fan works means that it is the control panel that is broken.
Right?

cineo wrote:finding this blessed "A4" and linking it to the ground.

C3CAR wrote:

The picture is from a reply by C3CAR in this topic:
https://citroenc3owners.com/citroen-c3-q ... 13-20.html

I looked in control panel and there are some parts a little melted. Even the pin 1 and 2 of my photos are, if you look a little burnt.

I think that is a good sign the control panel is busted.

You may be better off removing the blower motor and test it turns freely and run when connected to 12v battery.

It is possible that the fan is faulty and damaged the control panel.


I would check the fan motor on the bench and replace the control panel since you have already replaced the resistor pack.

I was able to start the fan! Yeah! By connecting pin A4 with the earth! So is the command that is broken! Thank you very much!
where can I find the replacement?

I was able to start the fan! Yeah! By connecting pin A4 with the earth! So is the command that is broken!

Great, well done!

Thank you very much!

No problem, thank you.

where can I find the replacement?

the ever useful eBay (here)

this is mine.

https://www.ebay.co.uk/itm/03-06-Citroen ... 35cd1079df

is very expensive.

if I put my broken panel and add a potentiometer 12V from pin "A4" to the earth?

if I put my broken panel and add a potentiometer 12V from pin "A4" to the earth?

I don't know, that's a lot of current to dissipate, let us know how you get on.

I would just keep looking on the ebay link until one comes up in your price range or open yours up and repair it if budget is tight.

With all those burnt connections it will be prudent to check all the wires for the heater and test the motor on the bench to see the bearings are free. You wouldn't want to melt another control panel.

I wanted to thank you C3driver52 for all the help you gave me! Thank you so much!
And then I wanted to ask if you think this control


is compatible with the other.

https://www.ebay.it/itm/Citroen-C3-Heate ... 1096331555

The recirculated air does not interest me. Since I find it easy to control while the other does not ...
Thanks a lot!