Undocumented Codes
 

Help! My 2001 XK8 is currently running in Reduced Performance mode and feels like it is going to stall. Getting error code of A331H/41777 and 9446H/37958. along with a few others: B2334 Column drive, tilt feedback potentiometer circuit failure - the steering wheel does not move when I put the key in.
U1041 - SCP vehicle speed signal - invalid or missing data. no clue
B1595 Ignition switch illegal input code. Huh?
U2012 ABS CAN bus error. Ok, which is?
B1853 Climate control circuit failure. AC seems ok
B1861 Climate control pressure switch - circuit short to ground. Huh?
C1175 Rear left wheel speed sensor input circuit failure. Is this that irritating ABS/ No Traction warning thing?

Any help would be most appreciated. My local garage had no clue with the undocumented codes.

You have so many different codes that I would start with the battery. Disconnect it and give it a full 24 hour charge then refit and try again.

By disconnecting the battery you will also be resetting the modules so effectively starting from scratch.

See how you go with that first and post up your findings.

What are they reading these codes with - a Ouija Board! :icon_lol:

Seriously, the 'undocumented codes' suggests the don't have the Jaguar DTC listings and may also be using an incompatible scantool.

Graham

+1 they just need to look them up properly

Ignore the daft ones and DIY look 'em up - see the free download workshop manual

(I'd change shop too.)

Sorry for the delayed response ; went on vacation and came hoe after a week and the battery was dead as a door knob. replaced battery and that cleared a lot of the codes. Still had the reduced performance mode and that turned out to be a bad coil.
replaced coil and spark plug.

running fine now, but suspect I will systematically go through all coils now. 'What is the next move - replace the remaining coils and spark plugs?
Is this an easy DYI effort?

thanks

Plugs are probably fine. Coils - maybe...

Good to hear it's running fine again.

Next move - buy a battery tender! It sounds like you don't run the vehicle as a DD or sufficiently to keep the battery at full charge. This is a regular cause of spurious error codes.

I wouldn't replace the remaining coils unless they fail. It's a lot of money for something which could last for several thousand more miles. However, if you do decide to replace them it's a very easy DIY. Here's the relevant JTIS sections:

Attachment 118126
Attachment 118127

The recommended service interval for spark plug changes on the N/A engine is 70k miles and there's rarely any need to change them more frequently.

Graham