I picked this car up about a month ago with the top not working and a dead battery, bought a new battery and installed it, no issues. I bought the car down south in Florida and drove it home to Nova Scotia (approx. 2300 miles) without an issue of any kind, no mil light, no error messages on dash. The car is an 02 XK8 convertible


I ordered a set of hydraulic lines for the top, stripped the interior and replaced all the lines, everything went smooth filled reservoir and top worked as it should, no issues with the car. This is where it all goes to crap, car sat for a couple of days, I go to start it and battery is a little weak, hook it to a charger and give it a slow and steady charge of 4amps for better part of the day. Start the car and system check fails every check, Trac not working, ABS failure, engine performance restricted. trans fault, brake fluid low, coolant level low and so on. I do a hard reset and seems to have cured the issue. I scanned the car and have various codes P1000 P1745 P1746 P1799 P0450 P1646 seems to be more communication errors rather then all systems failing, this was also the first time I scanned the car so some may have been old faults stored.


I drive the car for half an hour and everything seems fine, car sits for a few days and I start it and everything is back, all systems fail.


I had the battery disconnected while replacing hydraulic lines, had center console out, seats out, most of the interior stripped. I never had many wires unplugged except for the seats and lights etc on windshield post.


I have searched and read lots of posts, think I will start with the obvious things that I have had apart and check the wiring and also check the CAN wiring for issues.


Any other suggestions would be great. Pat

 

I'm no expert but really sounds like a bum battery. When you get failures can you get an output reading on the battery with a meter?

Best.

 

I don't suspect the battery but I will check it with a meter. The car starts right up, no sign of the battery being weak. No harm in checking it though.
Thanks

 

See if the crimps on any of the battery cable are getting warm with the car running. Sometimes the crimps go bad. Also check the megafuses at the rear of the trunk for tight connections, as well as the power feed to each fusebox.

 

So, today I started it with the same issues, did the reset with battery cables, still showed trans fault message but drove fine, I drive to work and start checking the battery and connections, the lead to the megafuses was loose so loose I could spin the nut off with my fingers, I took it apart and cleaned the wire and connection, replaced the lock nut, everything seems fine.


Scanned and cleared codes, P1000 is all that is left.
Lucky my 2300 mile drive home was with no issues.


I never touched this wire while doing the roof lines.