Citroen C5 2010 Air Con Problem

Post your Cit/Peu/Ren air conditioning queries or advice.

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Citroen C5 2010 Air Con Problem

Post by vbhatti »

Hello Guys,

Hope some of the bright minds here can help with a air con problem on my 2010 C5.
So far I have had a friend try to diagnose the problem without much luck so far.

When switching on the AC, the AC light comes on, but the air blowing into the car does not get cold.
The clutch on the compressor never engages, hence the compressor does not run.
I have had the gas checked and the pressure seems fine. Cannot recall the measurements.
The pressure sensor has been replaced with no positive affect.

We have connected a diagnosis machine to the car and ran a compressor test. A click from the compressor can be heard while the test runs, which I believe indicates the compressor is operational.

Any suggestions? What else can or should be checked?


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Re: Citroen C5 2010 Air Con Problem

Post by wurlycorner »

Wouldn't changing the pressure switch require de-gassing the system? (or if not de-gassed, would mean you had let all the gas out anyway?)

Best thing to do would be to plug in a lexia and monitor what happens, if you know anyone nearby that has one? Using that, you can tell if it's getting the right inputs to switch the a/c on and what pressure is in the system.

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Re: Citroen C5 2010 Air Con Problem

Post by mikevybiral »

Was this ever resolved?
(I have a similar problem).

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Re: Citroen C5 2010 Air Con Problem

Post by GiveMeABreak »

With the engine running and the A/C switched OFF on the climate panel, open the bonnet and look down at the compressor - it should not be running - the belt will be stationary. Now go back in and either push AUTO or switch the A/C on - go back out and see if the pulley and the compressor is now moving. You can hear it engage usually with a click when it is engaging.

If it is not turning, then the A/C ECU has likely disabled the compressor due to low gas which prevents damage from dry running - which indicates a leak and no gas in the system. If the pulley is running and the compressor is engaging, then you probably have a low gas condition and need a recharge. The system should be recharged every 2-3 years.

We don't know your country from your avatar (probably a good time to update it), but ATS and Kwik Fit do this in the UK.

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Re: Citroen C5 2010 Air Con Problem

Post by Brock »

I have the same problem but with the following symptoms as well:
When reverse gear is engaged cabin blower goes to max,
Cabin blower does not go to max by dashboard control,
ASR/ESP fails after a few miles of driving,
Parking sensors fail almost always straight away but sometimes work for a few seconds,
Rear wiper cycles when boot is closed.
Does anyone know the location of the cabin / an ancillary items ECU? Have the HUGE workshop manual with electrics part but can't get the thing to open :(

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Re: Citroen C5 2010 Air Con Problem

Post by GiveMeABreak »

What are you trying to do exactly? You can't open the BSI - there are no user-parts in there apart from the fuses which are on top. It is located in the pasenger compartment glovebox on the C5 X7 - which I assume this is the vehicle you are referring to as you don't say. The BSI is tha main brain of the car - be very careful what you do there or you may render the car inoperative!

The A/C system (if you have dual zone climate control) will go into air recycling mode when the air quality sensor detects pollutants like exhaust smoke - so this often happens in reverse and is done to limit the toxins from entering the passenger cabin. The fan air speed may alter in noise as it tries to rotate the air more rapidly while in this mode. So don't get that confused with a problem necessarily.

ESP / ABS / ASR faults are nothing to do with the A/C system - they will be another unrelated issue - you need to get the car fault read with Diagbox and post the codes up here.

What I would suggest is the battery disconnect / reconnect / BSI Reset procedure. Follow it exactly and this may reinitialise the BSI and vehicle data network ECUs.

Battery Disconnect / Reconnect Procedure

Finally a discharged or weakened battery will cause random electrical behaviour. You may, as part of the Battery disconnect procedure find it beneficial to remove the battery and put it on a trickle charge overnight. This can often cure may electrical faults - but observe the reconnection procedure as stated - or you can end up with problems.

Your A/C issue may just need gassing or you have a leak - I suggest you deal with these other issues first then get it checked, tested for leaks and refilled if necessary.