Hello guys,
I had the CATS system fault message when my front Air shocks were bad. I just replaced them myself today with new Arnotts and all is ok car runs fine BUT I still have the CATS System fault message.
Anyone! Do you think if I drive it for a while it will disappear itself OR it's something else that I am not aware of? I have a 2004 Jaguar XJ8 .

thanks, cheers

 

Have you tried a hard reset with it (disconnect battery, touch cables together, and leave disconnected for about 30 minutes)?

 

I replaced the front air springs yesterday and the battery was disconnected for about 3 hours but I did not touch cables together

 

As far as I know, the Arnotts units do not support ECATS functionality, so the CATS warning will never extinguish on its own. Arnott offers an Electronic Bypass Module (EBM) that fools the systems so no warnings will appear on the instrument cluster when their coil conversion units are used, but I believe the EBM can only be used if you convert all four corners to Arnott units. The original Jaguar/Bilstein units need the original Air Suspension Control Module (ASM) to operate properly. Check with Arnott to see if they can help with this issue and let us know the outcome.

Cheers,

Don

 

thank you Don,
I called Arnott and unfortunately the warning will keep appearing on the instrument cluster because the EBM is only for when coil conversion units are used.
My Jag runs fine all Arnotts air shocks are working fine.
Arnott said that I have to check with the dealer to see what code that issue might bring up.

 

Arnott makes perfectly serviceable air suspension rebuilds. They don't only make coilovers.

Do you have a Jag Indy that can pull codes and let us know what's going on?

If not, you may have a bad time.

You could try disconnecting both air shock hoses in the front, letting it sit down, be careful to get the electrical plugs plugged in right, disconnect the battery, touch the leads together for a few minutes, put it all back together and cross your fingers.

You really need a good diagnostic tool at this point.

 

As previously mentioned and confirmed by Arnott, the Arnott air springs/dampers do not support Jaguar ECATS functionality, so the CATS FAULT warning will constantly be displayed on the instrument cluster no matter what diagnostics are run or what codes are cleared. I thought Arnott had designed a small coil to connect to the ECATS connector to fool the ASM, but apparently the units rf69 received do not have this feature.

 

My two front air shocks are Arnott rebuilds. No faults, no problems, everything works as Jag designed.

OP, have the codes read by a dealer or someone with a Jag SDD, let us know what it's complaining about.

 

Thanks, i tried all that already. I do not have a Jag Indy to pull any codes but the CATS system fault message it's been there since before the replacement of the OEM old air shocks that were bad. I assumed that with the new Arnotts that message would disappear but it didn't.
I think I have a bad Suspension Module then.
but the car it's runing great and suspension is up fine
So i don't know what is bad about the Module.

 

I'm not sure, but I think Arnott no longer offer a rebuild service.

However their rebuilds would seem to have consisted of new air bladder plus general check-over for damper action, and external tidy-up. Bilstein built them originally and the air spring diaphragm is normally the first thing to fail, but the damper part is very long lived, but eventually this will start to fail so a rebuild isn't possible as to the best of my knowledge, this part of the unit cannot be dismantled and repaird. This may be why Arnott stopped rebuilding, but only Arnott can tell us, I'm only giving my thoughts.

 

oilstain,

Your Arnott-rebuilt Jaguar/Bilstein units still have their original ECATS solenoids, but rf69's new proprietary Arnott units do not have the solenoids or any adaptive damping capability. I suspect this must be why Arnott told rf69 they could not extinguish the CATS FAULT warning as he reported in post #5.

Cheers,

Don

 

There is no reason to suspect your ASM is bad. When it does not sense the correct impedance & continuity from the ECATS solenoids, it triggers the CATS FAULT. Since your proprietary Arnott air springs do not have ECATS solenoids, the ASM is not receiving the proper signals. I thought Arnott had resolved this issue with small coils that replicated the impedance of the solenoid coils, but perhaps they no longer offer these?

If your front end is still low, recalibrating the system with SDD as oilstain mentioned may solve that problem, but it sounds as though the CATS FAULT is something you may have to live with if Arnott can't offer a solution. The only other possible solution I can think of would be to measure the DC resistance across the terminals of the ECATS solenoids in your OE air springs and then try connecting a resistor of similar value across the terminals of the ECATS electrical connector on your wiring harnesses to see if that might satisfy the ASM and extinguish the warning.

Cheers,

Don

 

The resistor will likely "work" (avoid the error). If it's only a few ohms as I suspect, calculated the watts and buy the right resistor.

 

Maybe I'm dense, but nowhere in here do I read that Arnott has said that their shocks don't work with ECATS. What I read is that a customer called asking if the EBM will shut off a light (which he has no idea what it means, because he won't get the codes read), Arnott said no, that's for the coil conversion only, and sent him on his way to get the codes read (which he still won't)

Again, Arnott doesn't have ECATS and NON ECATS compliant models on their site, they have coil and air. Those are the only two options. I'm using two of their air shocks, no faults. I also have IDS, so I can read codes if I have them. But I was lucky enough to not have any codes pop up after install.

I'm sure I'm not the only one to order and install the air shocks from Arnott, this issue would be all over the boards if they sold replacement air shocks that didn't work with the system.

As far as the internals failing, if and when they do, send them back to Arnott. Lifetime warranty and all that.

Get your codes read! Who knows, your car may be complaining that one of the new shocks has a bad signal, you can then contact Arnott and try to get it resolved. Or maybe everything is fine, but the car is pissed off from the sensor reading being out of where they should be for so long that it just wants some reset procedure done.

 

Hi oilstain,

I may be the one who is dense, but I think we may be talking about apples and oranges. Until a year ago or so, Arnott offered a rebuild service for original Jaguar/Bilstein air springs/dampers. These retained the original ECATS solenoids and adaptive damping functionality. Arnott simultaneously offered their own proprietary air spring/damper design, which has never supported ECATS functionality. So, at that time, Arnott offered two air spring options, plus the coil spring conversion, for a total of three options. Beginning maybe a year ago, it has been widely reported on this forum that Arnott no longer offers the rebuild service and now only offers their own proprietary air spring units, plus the coil spring conversion. They have never openly promoted the fact that their own air spring units do not support ECATS, but as far as I know they've always been honest when customers have asked about it, and Doug from Arnott has posted this fact on this forum in response to inquiries. Arnott may include this info in a FAQ somewhere on their site.

I thought I recalled that at one point Arnott offered some sort of device to fool the ASM so it would not trigger the CATS FAULT, and photos were posted in a thread on this forum. The device was small and round and wrapped in white braided tape, as is commonly used on wire coils in devices like solenoids and transformers, with a socket to fit the ECATS electrical connector. We would think that if Arnott still offered these devices the rep would have mentioned this to rf69 during his phone conversation.

In your initial post you stated that your units are rebuilds, so they presumably retain their ECATS solenoids and functionality. On the other hand, on December 22, 2016, rf69 reported that he had replaced his units that day, so since Arnott no longer offers the rebuilt OE units, I concluded that his units were purchased fairly recently and are therefore the proprietary Arnott design that do not support ECATS. Thus, apples and oranges. Please let me know if I have misunderstood something.

I agree with you that it will be helpful for rf69 to have the codes scanned by a system capable of reading the proprietary Jaguar DTCs, since suspension codes tend to be C, B or U codes that generic OBDII scanners cannot read. I'll look forward to more information from rf69.

Cheers,

Don

 

Don, I have no idea anymore. I'm thoroughly confused. I've had no idea whether I've been buying rebuilds or proprietary, or what. I figured that Arnott takes Jag shocks, rebuilds them and sells them. That's why I claimed my shocks were rebuilds. Maybe they make the whole thing from scratch. I don't know; I don't care. Twice now, I've gone online and ordered the one thing they had: an air shock with a lifetime guarantee.

12/31/2014 I ordered a shock from Arnott. Installed, everything was fine. (FR)
12/1/2016 I ordered another shock from Arnott. Installed, everything was fine. (FL)

Apparently, somewhere awhile back, but not that far, but some time, they didn't work with CATS, unless they did, depending on which one you ordered, but not that you could know, since the website didn't state anything about CATS compliance or not.

Also apparently, Arnott has a device that can 'trick' the computer into working, but they don't usually install it on their shocks they sell to work with the computers of the car they know you are going to use them in, unless you ask them, and then they will say it doesn't work, except they know it could, but they don't put it on the shock when they sell it, to some people, or something.

This is absurd.

My experience: Arnott sells air shocks, they work with Jags.

In my opinion, if you buy an air shock from Arnott, it should work. If it doesn't, find out what's wrong (Scan), and talk to them.

At this point, and it's purely academic to me since my shocks work, but I'd like to read about Doug apologizing that his shocks don't work for the cars he's selling them for. If you have any links, pop them in a reply here. I haven't even tried to search yet, as you know searching for any air suspension problems on the forum brings up half the damn topics.

As for OP, if he can't be bothered to have someone scan for codes, then he is on his own. I can scan his car for him if he wants to make it to my neck of the desert, and let some idiot that doesn't know IDS very well try to scan his car. At least it would be cheap.

 

oilstain,

That is encouraging to know that a unit you purchased so recently connects to the ECATS harness and fools the ASM so no CATS FAULT is triggered. Hopefully that means rf69's units should also work. But why the Arnott rep wouldn't have stated this in response to his questions remains a mystery.

We'll both be anxious to hear the results when he has the codes scanned by a system capable of reading the proprietary Jaguar DTCs.

Cheers,

Don

 

Ok guys thank you for all the input i really appreciate that so far I called Arnott and they said to scan for a code and if it is related to one of the shocks installed they will send me a replacement , the warranty goes as long as I own the car. They also advised me that since the CATS System fault was there before the installation of the front shocks maybe I'm having problems with the rear ones that are actually Arnotts too replaced 3 years ago. In that case after I get the code I will tell them and if they can help with the issue in any way they will replace the bad air shock as long as the problem is related to the air shock not to any other electrical problem.

 

Time to eat crow!

I just got an email from someone at Arnott, the shocks they sell do not support CATS, they have a resistor in them to keep the computer quiet.

I didn't read that on the product description, so that kind of sucks. But it is what it is.

 

Well, I should eat some crow too, because we now know that rf69's Arnott units should have the resistors and should have resolved the CATS FAULT, so we're back to needing the codes as you have insisted.

Cheers,

Don