I have a 2004 XJ8 with 72K miles, The car was fitted with Arnott air suspension on all 4 corners in 2014.
I have read all the forum notes on air suspension but cannot find an answer to my problem.

I would assume the Cats system fault is because the arnott air suspension does not support the jaguar cats software/system....so how do I get rid of the error message in the dash and put out the yellow light...its annoying and has been like this since I purchased the car 2 years ago. The dealer said the error light was due to non standard Jaguar suspension parts fitted to the car?

I have tried to delete the error message using my foxwell NT510 but to no avail....any help will be much appreciated!!

 

Hello djpxk8,

Regarding: Well, it's true that "Jaguar" use(d) the "Bilstein" according to "X350_Dealer_Training_Air_Suspension_Section.p df", page 7-16
(https://en.jaguar-club.net/manual_download.php?id=272).

My suggestion is simply mail "Jaguar" in Coventry, UK, (JAGUAR Whitley Coventry <jagcrc@jaguarlandrover.com>), add your VIN
and a short description and I'm sure they'll reply your inquiry and if true is that reason.

The problem is that if you'll leave the "Check Engine" yellow warning light "ON", if another car's module will send a new
warning code... you'll simply miss it and sometimes it could be dangerous.

To, (temporary), get rid of it - you can use any car diagnostic tool to clear part/all error codes, (I'm using "iCarsoft" Multi-system Car
Diagnostic Tool L600 V2.0).

Wish you all the best.

 

You need to find an independent JLR specialist who is fluent in SDD programming to edit the Car Configuration File and change all references to CATS, Dynamic etc suspension to "Not Installed". Then the error messages will no longer appear. The dealer will not do it.

 

Do your Arnott shocks have the CATS plug in the top of the shock? If not, you'll need to reprogram the car as suggested above. If you do have the shocks with the CATS plug, these models have a coil inside to emulate the CATS shock solenoid and let the system think it's working normally. On both of my Arnott models, the coils shorted to ground via their metal bobbin--so the CATS system would throw a code for "solenoid shorted to ground" and make the CATS FAULT warning appear. The solution is to remove the coil and insulate the metal coil form with some electrical tape.

You can verify this is the fault by unplugging the CATS connector from the shock and measuring each pin to chassis ground. You should have no connection to ground--i.e. infinite resistance or open circuit on your meter. If you measure any resistance to ground, that's the problem. The coils should measure about 6 ohms pin-to-pin to verify the coil is still good.

The repair can be made on the car, just remove the 3 small hex screws from the shock cap and the coil is underneath. The coil just lifts out.

 

I have the arnott air suspension part #AS-2710, build date 13.06.2014. I have just called tech support at Arnott and they tell me they do not have the resistors for those suspension any longer! My Arnotts do have the metal cone on top and a wire plug also on top.

Besides the "cats system fault" on the dashboard I am also getting the "air suspension fault"

When I put my Foxwell 510 on I get these errors:

C1430 -Rear LH damper s/c to battery
C2303 - Reservoir plausibity error

C1430 sounds like to error you had with the s/c to battery, did you cure this fault with the insulation tape, and remove the error signal? if so how did you do it??

It sounds like I have 2 separate problems going on here.

When I purchased the car 2 yrs ago I already had the Cats error and the yellow light on plus the C1430 error. The dealer said it was because it had no standard air suspension. It looks like I may be able to solve this problem??

Many thanks for all your help!

 

Not sure if this applies to your 04 XJ8, but when I converted my 07 XJR to an Arnott coilover suspension, the new shocks came with an Electronic Bypass Module (EBM) that I had to install on the air suspension control module that is mounted behind the back seat. After installing it, all of the air suspension and CATS warnings stopped showing up on the dashboard.

Again, I don't know if this would apply in your situation, but it worked for me and the annoying air suspension and CATS warnings no longer display. No more CATS (which I miss having) but no more error messages, which I don't miss at all. Hope this helps.

 

You have the Arnott AS-2710 air strut but it doesn't have the cone and connector on top as shown in the photo below?

If the CATS fault was there before the changeover, and the code is indicating short to battery, this is different than the scenario I described where the coil shorts to ground. Sounds like you may have a chaffed wire shorting to 12v. Pull the plug on the LH rear shock and with key on, engine off, measure each pin of the harness connector to ground. One pin should have voltage and the other none.

 

mhamilton Thank you for your help!

YES, The AS-2710 I have fitted has the silver cone as in your picture. It also has a black plug connected to the cone with a wire coming out of it.


You stated "Pull the plug on the LH rear shock"...when I asked Arnott how to remove the plug, thay said I had to remove the cone by undoing the 3 alum screws....ARE YOU SAYING that I can just pull that plug off?,,,does it need to be turned first? or do I just yank it off? When I tried to remove the plug, it did not want to come off?


Also is the LH rear shock the one on the drivers side of the car?



Regards, David

 

Left hand is the driver's side in the USA. Left and Right are determined while sitting in the driver's seat. We have a starting point. You do have the air shocks with the coil in the top. You do not need the box WLinSTL mentioned because you are not trying to fool the air suspension module--your air suspension will continue to function as normal, the Arnott just do not have the active damping of ECATS. They have a coil in each shock that allows the ECATS system to think it still works normally. (Side note: your code C2303 indicates the suspension pump is not filling the reservoir, another issue altogether and very common. Either rebuild the pump or replace. Search this forum for more info on that).

I don't know what Arnott told you, but I wouldn't be inclined to ask them as they don't want end users to try and service the air shock. You would unplug the connector and then remove the 3 screws in the cone to access the coil in top to make the insulation repair I mentioned in my 1st post. That is for a short to ground. You don't have that issue at this time.

The code you have, LH Rear shorted to battery, indicates the ASM module (controls air suspension and ECATS) is seeing battery voltage where it shouldn't. This points to an issue with the car's harness and not the shock itself. Make the voltage measurement at the pins on the connector on the harness side. If you check the two pins of the coil in the top of the shock you should measure approx 6 ohms, if you measure S/C (0 ohms) this is your problem. To remove the connector from the shock just squeeze the sides of the connector and pull straight out of the shock housing.

 

Contact Cambo who might refer you to someone in your state that can do the SDD car configuration edit.

https://www.jaguarforums.com/forum/members/cambo-95188/

 

I finally get the connector off the top of the damper and when I measure the voltage Across both pins I get a full 12vdc (with the car ignition OFF)
When I measure the resistance across the same 2 pins I get a short circuit,

When I undo the 2 screws on the metal cone and remove it and take out resistor and measure across the 2 pins I get an open circuit (I believe you think this is the problem?)

When checking the voltage on the 2 pins of the connector:
With the Black probe on the meter on the earth of the car, I measure 12vdc on one pin and 0vdc on the other.(car ignition switched off)

When I switch the ignition switch ON the car and plug in my Foxwell 510 I now get the following readings; (with all parts disconnected, connector, resistor out etc)

C2303 Reservior..........
C1430 Rear left damper short circuit
C1432 Rear left damper open circuit

I hope this helps?? Where would I get a new resistor from if Arnott no longer supplies these??

 

I should have checked the code definitions first... C1430 is the original code, and the Jaguar definition is "LH Rear Air spring solenoid circuit malfunction - open circuit". Not short to battery. The coil went open, that was the original problem that set the CATS error. Replace it with a 6 ohm resistor and see if that resolves it. I can't guarantee a resistor will work properly in this circuit, I've never tried. I would try a 6 ohm, 5W resistor to start with.

C1432 is LH rear short to ground. Probably set when you were making measurements. Both of these should go away on their own when the circuit is repaired.

 

So today, I decided to swap the resistors in the rear dampers. I took the faulty o/c resistor out of the Left Rear damper and put it in the Right Rear damper, and the "good' resistor out of the Rear Right damper into the Left Rear Damper.




Erased any codes outstanding, took the car for a run for about 10mins, checked error messages and got:




C1427 Right Rear Damper Open Circuit

C2303 Reservoir plausibility error




I believe that proves that the original resistor in the Left Rear damper is open circuit and this resistor needs replacing!!! (QED)??




I called Arnott again and they tell me that they no longer have those resistors in stock as they stopped making the AS-2710 about 4 years ago.




Therefore the options are finding a 6 ohm resistor from an Arnott damper that has been replaced, but the resistor is ok? or trying out soldering a 6 ohm 5 watt resistor across the connector pins?




Arnott states that the resistor does not affect the action of the damper and is only for feedback to the control module, hence the resistor can be wired to the connector away from the damper....does this make sense?




Anyone on the forum have one of these resistors, see attached picture

 

Today was not my best day, I needed a 6 ohm resistor so I went to the local radio shack store to find it is now a Sprint store and radio shack went out of business 2 years ago....

A guy in the store recommended " Skycraft" in Orlando. They were great, I got a selection of resistors, the first one I connected the 5 ohm SOLVED the PROBLEM the yellow light went out and the "CATS SYSTEM FAULT: which has been on the car for 2 yrs since I bought it WENT OUT!!!! (see picture)




Unfortunately the resistor got so hot that it burnt a hole in the Air Suspension pipe...That's my fault for allowing them to be so close!!

Now I have changed the 5 ohm for a 7.5ohm ceramic resistor, again the problem with Cats fault is solved but even the ceramic resistor is getting very hot!!

I assume I need a higher wattage resistor and will try for a 6ohm, 25 watt resistor from the internet?? Do you think that is the answer??




ist try got so hot it melted a hole in the air suspension tube!!

Ceramic resistor still gets too hot....need a higher wattage say 25watt?? HELP!!

 

Glad you confirmed the problem. Sorry that you found out the hard way that a power resistor will get very hot.

One point just for the sake of exactness, the piece in the Arnott strut is a coil, not a resistor. Arnott used a coil (technically called an inductor) instead of a resistor to avoid the heat issue you experienced. I won't get into the technical differences or why they act differently... Yes they are correct that the coil is there just to fool the ASM into thinking the CATS system is fine. Long story short, the OEM shocks have a solenoid (coil) inside them that controls the fluid flow and makes the shocks firmer/softer. The Arnott replace that with the coil pictured so the ASM thinks the original shock is still there, but it's not controlling anything inside the shock.

Be careful, as a larger wattage resistor will not run any cooler, it will just handle the heat without failing. It could still easily get hot enough to melt a plastic part or set carpet on fire.

Couple of ideas:
1. If this were my vehicle, I'd try and repair the original coil. May require re-winding the coil with new wire if the break is in the middle of the coil.
2. If you want to try another option with the resistor, get one that you can mount to the body of the car so you don't have the heat buildup. Try www.mouser.com to search for Passive Components -> Chassis Mount Resistors. I found this 25W 6ohm option that might work: https://www.mouser.com/ProductDetail...O4J1WAZQ%3D%3D

 

 

DJPXK8, please where did you source the 8 Ohm 100 watt air cooled resistor?

 

Does anyone know what resistance range (voltage drop) the ASM is expecting to see? In other words "Would a 20 ohm resistor work?" The greater the resistance the lower the current (less heating) and therefore less problems dealing with a hot component. At 12 VDC and 6 ohms your carrying half an two amps of current.... and wasting it all as heat.

It wouldn't surprise me if the resistance needs to be 100's of ohms before the ASM senses an open.

Best Regards, William

 

Not sure if this is relevant to your question, but DTC C2304 (Damper Actuator Supply Circuit Short Circuit To Ground) which is sensed at the ASM Connector CR89 requires Pinpoint Test G256924p23; the first item in this test asks for you to check that you have more than 10,000 ohms between one of the two wires within the Air Shock Connector and Ground? (See below and Attachment)

 

Could you use the old external type ballast resistor, like the old cars used?

They were designed to drop the battery voltage, to the coil, from 12 to 6 volts.

Lots of heat generated there to disperse.

A coil mounted inside of a three sided ceramic type box, for cooling.

Has a metal strap with a hole in it for mounting to the fire wall.