Hi there,

I have a 2003 2.5 CRD Chrysler Grand Voyager and I have an Air Conditioning Problem.....

I first thought that it was just in need of a refill, so I took it to Quick Fit.

Quick Fit refilled it, saying that they detected no leaks and reclaimed no gas.

After that .... the A/C still didn't work so they put it back on the ramp and then told me that it had a leaky condenser.

I found a cheap UV pen-light at Maplins - well, I actually bought it! - and looked at the condenser with it.

There was a lot of florescence in the bottom corner of the condenser - so I went to a breakers yard and bought a replacement condenser.

I assumed that the gas in my system had leaked out, so I was a little surprised that there was quite a release of pressure when I removed my original condenser - but thought that it showed that the compressor was working (I had previously checked that the compressor clutch engaged when the A/C button was pressed.)

I fitted the 'new' condenser and went to a local garage that does Air Conditioning. I asked them to vacuum test the system and to refill it if it was okay.....which they did.......but they said that the system wasn't working properly as the radiator fans weren't coming on when the A/C was engaged.

So....back home and, with a very useful wiring diagram, some diagnostics....

The fans are okay, but Relay 1 does not receive a 'GND' when the A/C is switched on - so the system can't go into 'fans in series' mode let alone 'fans in parallel' mode.

More research led me to look at the A/C Pressure Transducer which sends a signal to the PCU to tell it to provide a ground signal that allows Relay 1 to trigger. When the pressure reaches a certain level, the fan should be triggered.

After taking the plug apart and leading out some wires that I could test, I found that the A/C Pressure Transducer was being supplied with the requisite 5V and a ground, but the 'sense' output was 0.9V whether the A/C was switched on or not..... So, it seems that the sensor might be stuck.

I got a quote for a replacement from the dealer ..... £144!!! :-o but was told that their Chrysler mechanic said that it was rare for these items to fail and wondered whether it was the compressor that wasn't working properly. I know that 'rare' doesn't mean that it won't happen but before another visit to the breakers yard, I thought I'd do another test.....

The compressor had provided quite a high pressure as I discovered when removing the old condenser, and it does seem to put a load on the engine when engaged, but when I did a high speed drive (to do the job of the radiator fans) the system did not cool....

So now I'm a little stumped.....

Can anyone give me an idea where the problem might be?

Thanks in advance!

 

have you had the fault codes read?, that should be your first step

The diagnostic/test manual con be found here

http://oskin.ru/pub/chrysler-dodge/m...05-RG-Body.pdf

Regards
Richard

 

Hi Richard,
Many thanks for the reply.
The Chrysler guy that I spoke to said that if the engine light isn't illuminated (apart from the during the initial key turn) then there will be no codes to read. Is that right? If not, are there other garages that can interrogate the codes, or will it be a 'Chrysler Dealer only' event?
Thanks.

 

The engine light only shows for emission related faults, the "key dance" will get you a few more engine codes. But all modules such as air con, abs, srs, instrument cluster, body control module all store codes which can be read by a scanner with proper software.

Most garages should be able to scan the codes - it's mainly the engine that they have trouble doing. Whereabouts are you? and I may be able to read them for you.

Regards
Richard

 

Hi Richard,
Farnborough, Hampshire - is that close?

 

tfb works nights in London, so about 90 mins on the M3

 

I'm in Cambridgeshire, but as Q says I work nights in London. Probably not worth your time. Ask a couple of local garages what they would charge for a code read of the air con system

Regards

Richard