Move Selector to "D" Transmission Fault Displays
 

Hello my learned friends.

97 Jaguar XK8 Convertible. As soon as I select "D" immediately displays Transmission Fault and car goes into limp home mode. Restarting after 60 second delay SOMETIMES clears fault, sometimes doesn't. Same result if selection is "R" and all lower gears. There are no codes on OBDII reader except P1111. Car is useless like this except for photo ops. Any valid suggestions are welcome and greatly appreciated.

Very respectfully, Bob G.

Best guess is that the code reader you're using is not picking up the codes. You may need try a dealer OBD read.

*** SOLVED, SOLVED *** P0706 Transmission Fault

Hello Everyone. I think it is VERY IMPORTANT that I share this SOLUTION with all of you.

I bought a 97 Jaguar XK8 Convertible four months ago. It is an absolutely splendid car. Then the P0706 Transmission Fault appeared. The car would immediately go into Limp home mode.

I researched everything I could find on the JAGUAR FORUMS and elsewhere. My mechanic said the problem was I needed to overhaul the transmission.

Well, I thanks him for the diagnosis.

With the car safely parked in the garage (again) I tried all of the following:
- Tested starting in Park, then shifting into D or R (failed)
- Tested starting in Neutral, then shifting into D or R (success)
- Disconnected battery
- Sprayed de grease fluid on the brake pedal micro switch under dashboard
- Sprayed de grease fluid on the console Park micro switch in console
- Sprayed both with WD-40
- Cleaned/sprayed shaft of Gear Change Control Solenoid-Automatic, P/N DBC11071
- Exercised gear shift many, many times through all positions
- Removed/replaced transmission control module and cleaned all contacts
- Grounded battery negative cable (not connected) to positive post for 30 seconds
- Reconnected battery
- Success

While I am uncertain which action solved the transmission fault problem, all of these actions were harmless, and none of them precipitated any other fault.

The problem was NOT CAUSED by the transmission cable, the rotary switch, or any other factor directly related to the transmission. The car did not need a replacement transmission as my mechanic suggested.

I strongly encourage anyone who has a P0706 Limp Home transmission fault to try all of these steps. It cost nothing except time, and the result is incredibly rewarding.

Very respectfully, Bob G.