C4 heater/air con not working

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Justin_Brown
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Re: C4 heater/air con not working

Post by Justin_Brown » 09 Nov 2017, 19:51

Thank you,

I'd appreciate that.
I would rather establish that it is indeed the fuse box before I incur any unnecessary expenses.

Are you suggesting bridging the circled wires?
IMG_20171109_204406.jpg

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GiveMeABreak
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Re: C4 heater/air con not working

Post by GiveMeABreak » 09 Nov 2017, 19:54

I've emailed the diagram to you as it is too large to display on the Forum.

PSF1 is the under engine Fuse box. Anything on the diagram with marching ants is optional kit - and won't be there (like the additional blower motor module we discussed earlier).
If you need a hand with the codes use this link to our Wiki, where I put a guide together:
https://frenchcarforum.co.uk/wiki/index ... ring_Codes

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petef
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Re: C4 heater/air con not working

Post by petef » 09 Nov 2017, 20:16

Yes, the two wires in your photo were connected with a fused bridge by the auto electrician and heater and air con then worked - but no delay when ignition was switched on. Can't remember the size of fuse - but should be the same as the heater fuse in the BSM, 15 amp??
When I eventually replaced the fusebox I simply removed the fuse and left the bridge in place - for the next time the fusebox fails.......

Justin_Brown
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Re: C4 heater/air con not working

Post by Justin_Brown » 09 Nov 2017, 20:41

I will use a 40 Amp fuse just to be safe and if it proves to be the fuse box I'll bite the bullet and source a replacement.

Justin_Brown
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Re: C4 heater/air con not working

Post by Justin_Brown » 10 Nov 2017, 17:19

Hi again,

Am I following instructions correctly?
I unplugged A from B and bridged connection A using a 30 amp fuse. My understanding is that this should have bypassed the fuse box and its relays providing the entire ac/blower set up with current. However all I got was an ABS and ESP fault message
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petef
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Re: C4 heater/air con not working

Post by petef » 10 Nov 2017, 19:22

The auto electrician bridged the two thick input wires - yours seem to be yellow and white? - with a fused wire (of similar diameter). However the plug was still left in the socket. If this does not work then the fault must be further down the line.

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petef
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Re: C4 heater/air con not working

Post by petef » 10 Nov 2017, 19:56

Just to be clear the bridging was done by splicing into the two wires.......

Justin_Brown
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Re: C4 heater/air con not working

Post by Justin_Brown » 10 Nov 2017, 20:55

Thank you for all your advice and patience. I gave the above a try and all seems to be working again.
I will run the temporary fix until I've sourced a replacement fuse box.

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petef
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Re: C4 heater/air con not working

Post by petef » 10 Nov 2017, 21:39

Good news. My money was on it being the same fault and therefore the same fix....

admiral51
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Re: C4 heater/air con not working

Post by admiral51 » 14 Jan 2018, 15:34

Well here we go, just when i thought everything was going well :)
My C4 blower has packed up.
It has A/C but manual controls and i am getting no lights on the control panel except for the rear screen heater which is working.
I am unsure of the blower location, cannot find it under the glove box so guess its situated in the centre looking at the photos already posted.
Just for clarity i am assuming that the bridging fix is basically crimp an in line fuse between both wires whilst keeping both wires connected to the plug in the fuse box pic.
Was thinking of trying this fix first, as everything seems to point to that being the problem.
Its a 2005 C4 and it stopped working whilst i was driving it, no intermittent problems, was working then stopped lol

admiral51
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Re: C4 heater/air con not working

Post by admiral51 » 15 Jan 2018, 12:01

The first 4 pics are the under bonnet fuse box, and as you can see someone has been there before me.
My intention was to bridge the 2 thick wires but not sure why the additional 40 amp in line fuse is there.
The last 2 pics are the in car fuse box and you can just see that 2 wires have been cut and soldiered but no additional wires.
Any help greatly appreciated
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taken by admiral51
DSC_0292.JPG
taken by admiral51
DSC_0293.JPG
taken by admiral51
DSC_0294.JPG
taken by admiral51
DSC_0295.JPG
taken by admiral51
DSC_0296.JPG
taken by admiral51

admiral51
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Re: C4 heater/air con not working

Post by admiral51 » 16 Jan 2018, 18:24

Spliced the wires with an inline fuse and we have everything working again.

Thanks for all the info, really helpful

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petef
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Re: C4 heater/air con not working

Post by petef » 17 Jan 2018, 10:11

Glad the in-line fuse trick worked, like it did with mine. Still think that in the long term replacing the fusebox, s/h from eBay, is a good idea.

C4sa
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Re: C4 heater/air con not working

Post by C4sa » 18 Jan 2018, 20:11

Thanks guys, the inline 30a fuse worked like a charm. Didn't need an electrician this time. Previous fuse box problem on my c4 was the fuel pump relay which the electrician bypassed by running a 15a fuse wired from the ignition to the fuel pump. 212000km and still going strong. Thanks again for posting the solution to the aircon problem.

Davyn1
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Re: C4 heater/air con not working

Post by Davyn1 » 06 Apr 2018, 12:22

Marc just bought one of these c4 for wife to run around in its a 2005 but heater only works on 4 assuming its the resistor are they hard to get at ??
Cheers