I have been collecting Failsafe mode codes on my '01 XKR. After spending many k$'s on many replacement parts I still have an intermittent issue that can betemporarily resolvedby cycling the car on/off several times. As soon as the Failsafe mode clears (and assoc. ABS & ASC warnings) it performs extremely well for another week or two. The latest fault codes are : B1229 CONTACT DIAGNOS.CO.UK FOR DESCRIPTION & P1229 TRHOTTLE MOTOR CONTROL CIRCUIT MALFUNCTION. My local shop has already replaced the throttle relay but this hasn't really resolved much. The errors generally occur when it is hot outside (most of the time here in TX) and after I have driven it 2-3 miles. Not sure if this is relevant or not.
I really enjoy the car a lot more when I am driving it and not when the shop guys are test driving it!
dugem260

 

Go to my web page and select Throttle Body. Not sure but it may apply.

 

sounds like you need a throttle body .. there a few thousands.

 

Hi,

Just wondering if you ever resolved your B1229 problem. I have exactly the same on my 1999 XK8 (now 25 years old!). I had both the P1229 and B1229 codes together with the Stability, traction and engine failure messages - limp home mode argh. I gave the throttle body and connectors a good clean and thought that I'd fixed the issue but it has come back 2 weeks later. However, this time it is just the B1229 that is appearing but this still induces the messages and limp home so I need to get this fixed.

Thanks for any help....

Martin

 

Isn't this solved by using a Battery Tender? That's how I roll.

 

^^^ this ! ^^^^

before doing anything else, just keep your car on a
well regarded battery tender whenever it’s not being used overnight or longer. CTEK, or NOCO Genesis 5 or 10, or a Delran Battery Tender + are the best ones I know of.

There are many theories why using a battery tender works to dispel electrical gremlins. Take your pick. But results speak for themselves.

Z.