2000 XJR

Good day everyone. I got a engine light one, scanned the codes coming out with p0105 P0400 P0678.

A little background,I fractured my wrist, was unable to drive for near 2 months. Battery was totally drained.had it jump started.

My (general) mechanic could not clear the codes and my inspection was expired and I can't pass it with the engine light on.

Please advise

 

I think you need a new mechanic with a new OBD II reader. Is your car supercharged (an XJR)? One code is for a faulty EGR found on the SC models. Another is for a bad glow plug found on diesels. The other is a bad MAP sensor input.

Maybe try a hard battery reset (unhook the negative cable and touch it to the positive post for ten seconds. Refasten after a minute or two). And then reread the codes with a good OBD II reader and if codes still persist, reset them. Then run it for a while to let the computer relearn.

It is quite possible your EGR needs cleaning and there might be a bad wire from the Manifold Air Pressure sensor to the ECU; the bad glow plug doesn't make any sense, nor does your mechanic's inability to reset the codes or look up their meaning . . .

 

Yes,mine is an XJR

 

P0678 is a false code reading. For the other two, this is what the Jaguar list says:

 

thanks, can you provide more repair instructions?

 

Hi Vincent,

If none of those codes was present before the car sat while your wrist healed, I would suggest you start by having your battery load tested. Jaguars are notorious for triggering spurious DTCs when the battery voltage and/or capacity declines much below full health. If your battery survived being fully depleted, and if you can get the codes cleared, they may not recur.

If your battery tests healthy and the codes recur, use the DTC Summaries guide at the link below - it includes possible causes of each DTC:

Jaguar AJ27 DTC Summaries 2000

Please keep us informed.

Cheers,

Don

 

Bad news is my mechanic can't or doesn't find the good way to figure out the way to fix it. Need to bring to the Jaguar specialist. And the only good one I know is far. Still look for another one with good review.

Ironically, there is the Jaguar dealership in my town, but I really don't want to break my bank

 

Your mechanic doesn't want to waste his time or your money. Bite the bullet and run it by the dealer. None of these issues are overwhelming.

Quite likely your EGR valve needs cleaning and you may need a new throttle valve. Some old guy at the dealer will know what to look for in a heart beat.

All assumes you have a good battery. Has it been tested?

 

yeah, this general mechanic place I have been going for years which i have a pretty good relationship so they dont want to risk their good name or wasting time. They are no expert to Jaguar, every time I have to tell them what to do/fix so they can do a good job but they are not good at diagnostic (especially on Jaguar)

battery was changed less than a few thousands miles ago, it still looks brand new and clean as hell.

 

You really can't judge a battery's electrical condition by its age or outward appearance, so I still recommend that you have it load tested. Except for the AGM type, batteries don't tolerate being deeply discharged very well, and Jaguars, more than most cars, require a really healthy battery.

Cheers,

Don

 

will check the battery, thanks