Any experts on here know if the air suspension module operating CATS can fail to switch the shocks from hard to soft setting without flagging a fault code ?

My 2003 Technical Notes tells me that the shocks default setting is 'Hard', which is then switched to 'Soft' by the ASM over a speed of about 1 mph, and then temporarily hardened up depending on what the car is doing, like braking or going round bends quickly.
I am finding the ride overly hard at the moment, and do wonder if the system is 'forgetting' to switch the shocks to 'Soft'. Maybe it's just me as I'm getting old and want more comfort, but it seems much harder now than two years ago.
OK, it's a Sport, so much firmer than the standard suspension, but last year it seemed OK.

I have no faults displayed at all, so you are probably all thinking "he should be so lucky" !!

 

Hi Fraser

A number of people have reported this type of fault and I have an idea that if

you get a cats fault the system stays hard until the code is cleared.

Obviously you have not had a fault on the dash but this is the only comment I

can make I'm afraid.

BTW I have had a look at your Jag specialist near you and would like to have my wheels aligned on their super duper machine but it is a bit difficult from here!

 

Maybe your driving 'aggressively' and you've entered the stiffer mode by your driving style recognized by the ECM and related modules?

 

Well, I drive briskly on the main roads, but do a lot of pootling along country lanes and it is hard and unyielding then, not at speed.

 

I was thinking about this on my drive to work in my XJ. If it were me in your shoes, I'd start off with a module reflash using the dealer software. I was considering a manual reboot, or perhaps evacuating the air from the entire system by bleeding the lines and tank, then allowing the system to refill...but somehow, those don't seem like suitable efforts when your trying to determine why the suspension module thinks it should go into its 'stiff' mode at the incorrect times. If only you had another module you could 'swap' with yours to rule out all wiring, sensors, and external influence from the module. Any chance you can track down another member who can allow a temporary transnsplant? An 03 or 04 should be compatible...but I'm guessing in that area. I only guess since mine has a vin split in the 2005 MY for lots of 2004 system features like the stepper motor in the headlamps and ballast type.

 

I can concur with this. Happened to me a couple of times, the car went rock-solid when I got an Air Suspension Failure message, and stayed firm even after the warning went off. It wasn't until the code was cleared that it went back to normal.

 

Many thanks. I haven't had a suspension fault message since 2010 when the air compressor was replaced. However I have had, (last year in Germany) a "DSC not available" message. This, however, disappeared on its own.
Anyway, I'm going to get the suspension checked out next month when I take the car in for service. Have there been any TSBs on CATS ? The system was installed on the previous model X308, I believe, albeit not with air springs.