my 2010 xfr downshifts really hard and jerks when i am almost completely stopped. i read that instead of having it reprogrammed at a dealership you can "flash" the ecu yourself by disconnecting the battery cables and touching them together to complete the ground and release all the stored energy in the capacitors to reset this issue. im not saying i believe it but i am curious and want to try it. any thoughts?

 

Sounds like The Lurch which would be pretty shocking since it was meant to have been solved years ago...

You can't reset the TCM just by disconnecting the battery & touching the cables, that will clear the adaptations in the engine ECU, but the TCM adaptations can only be cleared with the SDD diagnostic system.

 

How or where can i get this done without paying out the @$$ for it?

 

I have the same exact issue with my 2010 XFR, and it started about 8k miles ago. I am under warranty and my tech told me he will hook the lap-top to it and review the adaptations which will clearly give him access to the TCM.

If you are out of warranty I would call Jaguar corporate and demand they fix the issue. IT IS FLAT OUT UN-SAFE for a car to behave this way. I just need to get back to the dealer to get it fixed. I love the car but with 28k miles on it and a squeaky windshield to boot it does take away from loving the car even more. My 2003 Cobra has 570 HP and is tight as a drum. The XFR is almost 3 times the price new so I do expect better.