Fault F994 - AC Compressor

[ne8ryan]

Hello,
Just came back from getting my AC diagnosed as it has been failing to work for the last year, and with the current UK climate, it was horrid drive in 30c weather.

The diagnostic came back with the following code;
Fault F994 - Fault in A/C compressor clutch control

I was quoted £500 to replace, regas & labour - about a full day of work.
Is this reasonable or would it be cheaper to buy a spare compressor off of the internet and see if another garage could fit it and then regas it via ATS Groupon Code (about £45)

The garage said it is either the compressor or the clutch, either way the compressor has to come out.


Cheers.

[mickthemaverick]

Hi, you may find some guidance from my dealing with a similar problem on my C5. You can read the thread here.

[ne8ryan]

Hi, you may find some guidance from my dealing with a similar problem on my C5. You can read the thread here.

Hey Mick, thanks for the link.
Not mechanically inclined unfortunately so all of that has went over my head.

What's the average length of time it took you to replace/repair, as my usual mechanic has never done a compressor in a DS3 so he's not too sure how long it will take to give a proper quote,
also what is the average price for a compressor, new or partially used?

[mickthemaverick]

I paid around £70 for the replacement clutch I think which was new, the compressor was around £100 second hand at the time as I believe a new one was in the 3-400 range. It took me an hour to dismantle, and a couple of hours rebuilding and refitting so I'd suggest a morning's work is about right. Maybe get your mechanic to read my thread and base his quote from there?

[ne8ryan]

I paid around £70 for the replacement clutch I think which was new, the compressor was around £100 second hand at the time as I believe a new one was in the 3-400 range. It took me an hour to dismantle, and a couple of hours rebuilding and refitting so I'd suggest a morning's work is about right. Maybe get your mechanic to read my thread and base his quote from there?

Ah okay so the clutch and compressor are seperate components, could be around £200 for the parts, do you remember the part numbers for both,
I will pop down this week and let him read it, see he is aware.

[mickthemaverick]

I only had to replace the clutch coil which had gone open circuit and the condenser due to a leak, the compressor was fine. However I replaced the clutch as it was easy before rebuilding the unit. The only part numbers I had were those on the diagram Marc posted at the start of my thread. However my car was a 2003 C5 so unlikely that the same numbers will apply to your car although the system principles are the same. Once the compressor is removed from the car it can be examined manually to see if it functions ok and hence you will only need to replace the clutch or maybe just the coil. More often than not it is the clutch coil that fails and you may be able to simply replace that although while in there it makes sense to renew the clutch itself. Testing for continuity through the coil by unplugging it is worth doing before any dismantling takes place. Good luck

[ozvtr]

You can get the coil by itself but if you buy a compressor it will come with the coil.
The fault could also be in the BSM or the wiring from the BSM to the clutch coil. Are they sure it's the clutch coil?
It is a very simple process to find the fault...unfortunately, there are a lot of incompetent technicians out there!
If it's the coil and that company has access to a coil (which they should), the coil could be replaced without removing the compressor and the system would not need to be re-gassed.
However, some companies only replace whole components (the compressor in this case) so that they can push warranty claims back on the manufacture of that component and limit their own liability. And some don't have the skills to replace just the coil!
You would be looking at about 200 pound for the compressor, 75 pound to re-gas the system and about 50 pound an hour for labor. Those prices are VERY approximate! But you can see your 500 pound would be gobbled up pretty quickly.

[ne8ryan]

You can get the coil by itself but if you buy a compressor it will come with the coil.
The fault could also be in the BSM or the wiring from the BSM to the clutch coil. Are they sure it's the clutch coil?
It is a very simple process to find the fault...unfortunately, there are a lot of incompetent technicians out there!
If it's the coil and that company has access to a coil (which they should), the coil could be replaced without removing the compressor and the system would not need to be re-gassed.
However, some companies only replace whole components (the compressor in this case) so that they can push warranty claims back on the manufacture of that component and limit their own liability. And some don't have the skills to replace just the coil!
You would be looking at about 200 pound for the compressor, 75 pound to re-gas the system and about 50 pound an hour for labor. Those prices are VERY approximate! But you can see your 500 pound would be gobbled up pretty quickly.

The original garage is an auto electrician but not a nation wide company, a back street garage sort of speak.
My local garage - the guy that does my MOTs, Services, repairs etc is going to give me a quote if he supplies the compressor.

Is it a potential gamble to do all of that labour, replace the coil and see if it works, not sure how much it would be labour wise, and I wouldn't know where to just get the clutch.

The full error code is as follows;

Engine wiring housing - BSM
Fault F994 Fault in A/C compressor clutch control

[mickthemaverick]

Is it a potential gamble to do all of that labour, replace the coil and see if it works, not sure how much it would be labour wise, and I wouldn't know where to just get the clutch.

The full error code is as follows;

Engine wiring housing - BSM
Fault F994 Fault in A/C compressor clutch control

As I said it is possible to test the coil with a multimeter before any work is done. That will tell you if it is a coil problem or a wiring/system issue. If it is a dead coil then the compressor had to come off on my C5 but maybe not necessary on yours. I wouldn't pay out for a whole compressor before testing it,

[xantia_v6]

I would firstly be suspicious of a faulty BSM not providing any voltage to the clutch coil.

[ne8ryan]

I would firstly be suspicious of a faulty BSM not providing any voltage to the clutch coil.

A few further details, when I tried to get it regassed, the technician said it wouldn't "go" or fill up, got the lines leak tested with yellow dye and couldn't see anything come out, the lad said no leak in the system,
not sure if these details make the situation worse or better.