Climate control

[Rekray1982]

Good evening, since i bought my car 57 plate C4 Picasso VTR+ from 2008 there has been an issue with the blower fan running at high speed. The climate control buttons wouldn't adjust the speed at all so today i changed the blower and resistor like for like. The part number for the resistor I matched and as there was no part number on the blower, I purchased the corresponding one advertised with the resistor. Fitted them today and the noise is considerably less from the fan but still wont adjust via the buttons for speed. I cant rule the buttons out of being faulty even though i can adjust temperature and put recirculation on but cant change speed or seem to adjust where the air comes from. It also seems to have poor air flow from vents. Is it possible the people who i bought it off have fitted the wrong item so wont work the blower or is it likely to be the buttons.

Thank you

[mickthemaverick]

Assuming this is your control panel, is it the arrowed buttons that don't work?

C4 Picasso control panel

[Rekray1982]

Mine doesnt have the display but a wheel instead for hot and cold. Yes those are the buttons that dont work and possibly the one for where the air comes from e.g. dash, windscreen or feet vents. I did take it out and remove the wiring harness and couldnt see any issues, no dirt or rust on the connections.

[mickthemaverick]

Like this one?

Non display version

[Rekray1982]

Yes, thats the one.

[mickthemaverick]

Then the first thing to do is make sure the connectors on the back are pushed home properly, you may have to prise the panel out with a trim tool to get access. If they are connected properly then it is possible that the switches themselves have died but as there is a line of switches not working I think a loose or even disconnected plug is more likely. You can replace the whole panel with a used one fairly cheaply to test it out, eg: https://www.ebay.co.uk/itm/256981576077 ... e6c2ad65e7

That listing does include the OEM part number if you would prefer to order a new one but expect you may need a mortgage!! Good luck

[Rekray1982]

Already had it out and inside the connections looks perfectly clean and no rust or dirt inside. Wiring and connection into the part as well looks fine, its on a lever type locking system so could only put it in as far is it would go and then push lever back to lock it. Another point to add is as far as i can tell the only buttons that work are the rear screen defrost, the hot and cold wheel and the recirc button, if that makes any difference. All lights on it work when buttons are pressed as well.

[mickthemaverick]

By all lights does that include the little arrows top right corner which do change when you press the output selection button?
Is this like the control you have replaced?

https://www.amazon.co.uk/Control-Module ... B0FDH2M4J4

[Rekray1982]

I've found one on ebay for cheaper, with the same part number. They accept returns so no harm in trying for losing a couple of quid on a returns label. Yes all the lights work fine when buttons are pressed, even the speed control ones.

[Rekray1982]

yes thats the one i replaced and the corresponding blower for it as well.

[mickthemaverick]

If those lights work then the switches would seem to be OK but not connecting to the control unit. I'm not sure that the new panel will make any difference but as you say if cheap enough that is one way to find out!

[Rekray1982]

So if it turns out the same switch is the same and doesnt control speed, then as the fan is blowing at a speed even though less quiet then the old blower, which could be due to new versus old. Its looking like the connection between the resistor and the switches. Are they on the same loom and only run between the blower and switch. One wire connects resistor and blower. other 2 connections join the same wiring sheath, are they likely responsible then.

[mickthemaverick]

You need a wiring diagram to determine the routing which the forum does not have access to at the moment. We are working to get our access back but at the moment I can't look it up. Another member who does have access may see this and help out. In the meantime applying some basic logic:
It is possible that the switch module is fed with a power supply from the dash lighting circuit to power the lamps, whereas the motor control will be powered from its own fuse which may or may not be the same one for the motor itself. Worth making sure you don't have a blown fuse for the control box etc. Finally there could be an intermediary multi connector which links the dash loom through to the engine compartment loom and hence could be a suspect. Really need a diagram, I'll have a search and see if something comes up.

[Rekray1982]

That's far above my pay grade, i'll try the new panel and if it doesnt have the desired affect there is a decent auto electrician near me who also specialise in climate systems. Ill get them to diagnose it all and find a solution. I have an issue with a central locking issue on passenger door only and get them to check it all out at the same time.
Thank you for all your help and patience.

[mickthemaverick]

OK no problem, good luck with it