All fault warning lights lighting up the dash at once after battery replacement and air suspension pump replacement

[daylawrence]

Hi, I have a 2004 XJ8 (XK350) 4.2 SE petrol 58k miles, which up until last week ran perfectly. Then I hit  a pot hole and my air suspension warning light came on and then went off. Eventually the fault light came on again and again and so it was diagnosed as having a weak air pump. This was replaced last week and the car drove a few miles without fault. Then I noticed a drop in power as I went round right hand bends particularly and the car went into limp mode soon after. The DSC warning light came on, then park brake warning light came on, then engine systems fault light, then restricted performance and so on. I left the car for two days and went back to it, to drive to my local jaguar specialist who repaired the air pump and I was shocked to see that the warning lights had all disappeared. So I took it for a "do or die" drive about 50 miles and it did not miss a beat!

Yesterday I took it for a short trip to the shops but it barely made it home, with all the lights going on and driving about 5 miles an hour. I suspected that even though I had given it a good run without fault, the battery was not in good health so I ordered a new battery and changed it over today. When I went to start the car, it would not start and as I say every warning light possible was on. 

I called the RAC and the mechanic could not communicate with the computer and it would not allow him to clear the error or read any error codes. He could not select a gear either so he was stumped.

Your help and advice would be very much appreciated. Thanks Anthony

 

 

[Jimbov8]

I would be checking the condition of the ground points behind the headlights, these are known to fail. They may look ok but corrode from the inside out, show them a spanner and they fall apart. It could be that the jolt has dislodged one.

[Max Lloyd]

 HAVE THE SAME PROBLEM. I'VE JUST COMPLETED A PARCIAL RENOVATION. I'M LEFT WITH A NONE START FAULT (SEEMS TO BE THE SECURITY SYSTEM) AND ALL THE WARNING LIGHTS SCROLLING. PN ADDITION MY key FOB WON'T REPROGRAMME WHICH MEANS THAT I CAN'T GET THE SEC. SYSTEM TO RESET.I'VE CHECKED THE BATTERY AND CHECKED FOR SHORTS AND OPEN CIRCUITS REMOVED AND CLEANED SEC. MODULE, key TRANSPONDER MODULE. THE CAR IS STILL STANDING. IF I GET ANYWHERE I WILL LET YOU KNOW. PLEASE DO THE SAME FOR ME IF YOU SUCCEED. I CAN'T GET LOCAL GARAGES TO EVEN TRY.

I WISH YOU ALL THE BEST WITH YOUR PROBLEM AND HAVE A GREAT NEW YEAR.

[daylawrence]

Thanks for the replies, I  tried again 24 hours after RAC attended but had the same error messages scrolling etc. So I disconnected the battery. I have a new battery coming today and fingers crossed, the system might be fooled into clearing some of the fault warning lights. If that does not work I will check the condition of the grounding etc but the biggest problem is that with not being able to start it the handbrake fault light is on, meaning I cannot release the handbrake and also the gearbox fault light is on as well. The RAC guy says I will need a specialist recovery firm to get it out of my drive, does anyone know who might be able to help?