So my 08 XJ8(X358) must know I am trying to sell it as after months and months of trouble free operation I now have a xmas tree dash. Here is what I know and am hoping someone with have some input.

120K on the car and in great overall condition, no water contamination issues and new battery in fall of 2018. Driven daily. Had parked for just a couple of days to drive one of the other toys. Suddenly got the ABS Fault light along with related systems not available messages. Upon start up the car does not show fault until car reaches 5 mph which I assume is when various components "check In". Car is running fine otherwise.

My basic reader does not show ABS faults so I took the car to my local Jaguar specialist Motorcars Intl. in Plainville Ct. As an aside, Mike the service manager was terrific and happily read codes for me. I was hoping it would point to a wheel sensor/wheel bearing etc but that is not what I got back. oh boy!

C0001-01 Traction Control Switch Channel A Valve Fault, C0002-01 Traction Control Switch Channel B Valve 1 Fault, and C0082-48 Brake System Malfunction Indicator Fault.

So into my shop manual I go and all three faults have "HCU internal failure possible" as their description. So now I finally get to some questions.

• Does HCU refer to the physical valve and its motor, or to the electric control module for the valve?
• If it is the control module, has anyone experienced an internal solder failure similar to those described in X350 series?
• My grounds behind headlights look fine but I have never taken them off and cleaned. Any hope of a miracle cure here?
• I will also check that the fuses that control the various electrical inputs to the ABS module (3 or 4 I think) are okay.

I am just wondering if anyone else had this form of failure and whether anyone has any suggestions. Really don't want to sell it with issues.

 

These people can fix it:

BBA Remanufacturing Inc
300 Myles Standish Blvd
Taunton, MA 02780
United States
1 508 822 4490
Fax 1 508 822 4491
us-sales@bba-reman.com

 

Thank you for that info. If I determine it is the control module that may be what I do. I almost wish it were just the ECU. I really want to get this car in a new home and put my attention to an XJR that I picked up and now money is going to flow in the wrong direction...

My concern is that it is the pump based on the codes. Because they say traction control it tells me it is rear wheel related but a channel fault makes me afraid that one of the solenoid valves inside the pump has failed or is stuck etc...

Ive never flushed the brake fluid in my short ownership and don't know if original owner ever did. At 121k miles, moisture in and breakdown of the fluid could possibly cause an issue in the valves but Im not familiar enough with this system to know if those codes could be masking something simple. And while I could physically install a pump, I dont have the software/tools to properly bleed the unit.

I have more reading in the service manual and electrical guide to do. I also have a date under the hood tomorrow so we will see.

Thanks again for the info on BBA

 

Greetings all,

I recently have had a similar issue. I get regularly, but not always, messages and warning lights of parking brake failure, air suspension failure, abs, dsc, and some others. Sometimes, often, the messages or dash lights are for a second or two only.

I haven't yet had the codes read.

Any thoughts or experience with this problem? Is the cause a wiring issue, failing computer?

The car is running well otherwise.

Thanks

 

I'll mention this again, but mine cleared up after I changed the batteries in the remotes. They were functioning fine otherwise, but I figured what the heck, that's a repair for under $20. I have seen some confirmation, on other luxury brands from this era. Apparently the coded key has to be in the car reader, doesn't like weak signals. Please don't beat me to death on this, it sounds crazy to me as well, maybe it is Voodoo. Anyhow the next few times I drove it, the learning sequence started, the engine searching for the proper idle speed, the trans trying to fuzzy logic my driving style. All I know is; I haven't had an incident since.
P.S. you are really lucky you didn't get the 'locked in park' treatment, out away from home. I did just before I stumbled onto this.

 

Check the electrical connector on the ABS unit (HCU). Could be loose or have corrosion.

 

That reminds me -there have been a couple of instances of bad contact on the ABS pins

 

I had similar problem in a 2007 BMW, and 2005 Audi. Both were heat related, codes came up after driving a little. But progressed to full time. They call it a Trifecta. ABS, parking brake and traction control. Lots of lights and warnings.
Wife drove the 335i for five years with this. Would pass Texas inspection. The A8 would beep loudly at 5 mph, only could take a year of this.
Sent both ABS modules off to Module Masters in Idaho. Reinstalled and they were fixed.
They seem to be very though. I did not get a plug snapped on securely on the A8. Called them and the lady told me the Module works perfectly now. They had repaired failed circuits. Check the wiring. Pressure sensor plug on ABS pump slid right off in my hand. Snapped it on and all has been good.
I was impressed that she could pull repair ticket and see pre and post repair testing. Hope the Houston heat does not cook the ABS controller on the XJR. Mounting location seems better than the BMW and Audi.

 

Module Master rebuilds The ATE ABS module in a 2006. But does not show the 2008 Module. Assume they do not service these.
There used to be a one man shop called Cheap ABS. They were half the price of Module Master. But closed.Try BBE.