Out for a drive because it's a beautiful 65F day and I noticed the jag telling me the outside temperature was 0F. Now unless I drove through some weird weather pattern something isn't right. I hooked the iCarsoft up and did a scan and got the following:
ABS
INTERMITTENT-U0104-00:Lost communication with speed control front distance range
BPM
PERMANENT-U0197-00: Lost communication with telephone module
FLR
INTERMITTENT-U0401-81: Invalid data received from ECM - speed control inhibited by ECM
BCMB
INTERMITTENT-B2A90-16: Circuit voltage below threshold
PDM
INTERMITTENT-B1C15-15: Passenger Up/Down Mirror Motor Feedback Circuit
RFA
INTERMITTENT-U201F-13: Receiver communication error
FACP
HISTORIC-U0155-00: Lost communication with Instrument Cluster
ICM
PERMANENT-U0197-00:Lost communication with telephone module
BCM:
INTERMITTENT-B1009-64: Ignition authorisation signal plausibility failure:
• CJB fault
• Low speed CAN fault
• Instrument cluster fault
CCM:
INTERMITTENT-U0401-81: Invalid data received from ECM - speed control inhibited by ECM
NCM
INTERMITTENT-U3000-49: Control module Internal electronic failure

Now my gut is telling me it's the battery because I know Jags and Land Rovers tend to act weird when they're not happy with the battery voltage. The PO told me he replaced the battery at the end of last year so after double checking the Interstate Battery website I see what is installed does not fit an XKR (at least according to Interstate Batteries).
https://www.interstatebatteries.com/products/mtp-49/h8





I checked all the fuses and saw nothing amiss so wanted to see if there is anything else I should check. I ran a voltage check from cold start and running around for a bit and this is what it looks like:


Car runs fine and there isn't a check engine light so before I load the parts cannon thought I'd see if there was anything else to look at before I do that.

 

Check the battery with the car not running, if the V is below 12.5 you may get all sorts of scary codes. If above, Good Luck and enjoy the challenge.
WJ

 

Welp, looks like that could be the problem. I suppose a new battery is cheaper than a bunch of new modules . Thanks!

 

and make certain that the new battery is fully charged!
WJ

 

I have the same battery in my 2014, but in the AGM variety. When I bought my car, used, 3-4 years ago in came with a non AGM, same number.


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There was a TSB issued about this and the solution was to do a firmware update.

 

Suggest you charge the battery, then clear and reread codes after a short drive. Most cars store historical codes.

 

Prior to condemning the battery outright, charge it for five hours at 2 to 5 amps and then retest. Retest the battery with a voltmeter across the terminals and the ignition in the OFF position. If there's still less than 12.6 volts available, replace the battery.

 

I have the same battery in my 2014, but in the AGM variety. When I bought my car, used, 3-4 years ago it came with a non AGM, same number. The original battery was replaced with this battery after 1 year. I think the battery you have is a more powerful battery.


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So that second reading I took was after a 20 minute drive, battery was reading at around 14v but when powered off it's below 12.5V. I'll break out the multi meter tomorrow after a drive and then put the trickle charger on after.

 

Do NOT use a Trickle Charger. Ever. Not ever.
First thing.... trickle chargers never turn off so they burn batteries dry. Bad.
Second thing... trickle chargers take forever to charge a low battery. Bad.
Get a battery CHARGER, like 5-10 amps.
Third thing... Get a battery MAINTAINER which will keep a nearly full battery topped off. Those will also not CHARGE a battery, but only bump it up a bit.

 

Found it:

https://www.jaguarforums.com/forum/x...36/#post604210

 

That was a misspeak on my part, I have ctek US3300 maintainer (my brain told me trickle charger). I took the car for a 10 mile drive this morning and this is what I found with the multi meter on the battery terminals.

Last night around 10pm I took a reading of 12.49V
Before I left this morning I took a reading of 12.28V
Immediately after my drive this morning I took a reading of 12.61V.
About 5 minutes later I took another reading of 12.41V.

I have the car hooked up to the ctek maintainer (it's nowhere near the battery sitting in the front passenger foot well) and will check again around 2pm. When I hooked it up it showed as charging on the indicator light.

 

the last line from ceejay!
either get a charger and use it or a new battery.
wj

 

Thanks, I'll take a look into this as well.

 

Okay, will do. Thanks.

 

Okay so after letting it sit on the charger at 2amps for 5 hours the battery at the terminals read at 13.33V, cleared the codes and took it for around a 8 mile drive. Got home and read the codes again and saw the following:

CCM (Speed Control Module)
U0401-81:
State: Intermittent
Invalid data received from the engine control module/powertrain control module

U0415-81
State: Intermittent
Invalid data received from ABS control module.

No historic faults that I can see.
I waited around 5 minutes after scanning before testing the battery terminals again and I got 12.55V on the multimeter. About 30 minutes later I checked again with the multimeter and the battery gave a reading of 12.36V.

Ground and power cables look clean on the terminals, I'll let the vehicle sit over night and will test the battery voltage in the morning to see if this isn't some sort of parasitic draw. Next step is a new battery if the voltage holds overnight.

 

I just read a "Recommended Article" on my phone... "Seven Jags to Avoid and Why".
Evidently the only thing wrong, which made the XK undesirable, was "Wheels, Tires and Brakes".
WTF??? Evidently some schmo got tasked with writing an article about what he's never experienced.

 

Sorry to throw money at this but I would buy a new battery, charge it fully, install, use it several drive cycles and then read the codes.
WJ

 

Thanks for the help, and I did buy this car fully expecting to have to spend some money on it. The passenger side mirror doesn't dip in reverse but can be adjusted with the controls, if it's not the battery it may be that module but only one way to find out.