I have a 98 XJ8 had a no start issue which has been sorted out still have a failsafe engine mode and a new gearbox error code shifter doesn’t just seem right in fact the selector and gears are not aligned . I have already found a shifter assembly for $40 would an adjustment work or is replacing the whole unit the way to go car was running great with no transmission problems at all.

 

Your problem could possibly be the selector cable. It stretches over time and makes gear selection a bit random or non existant. Adjustment of the cable may work, otherwise change it as the ball and socket can get rusty and jam up causing difficult gear selection.

 

I picked up the used shifter assembly also did a ton of searching and reading here on this fine forum looks like your right on. I took apart the console to get a closer look at the shifter assembly which can't be moved without the key inserted car on foot on brake pedal started the car up shifter assembly moves smooth through all selections on the J gate only problem is car doesn't move at all only the N is lit up. Yesterday it would only start in neutral at least the car would move using manual selection or reverse again only N lit at any time.

It almost feels like the cable came loose at the tranny under the car cable at the shifter moves through the gear range no problem. I pulled some codes got PO706,P0302,P1316 been chasing that coil issue the 706 is new fail-safe engine mode is gone should have moved the car into the garage to work on it due to the weather it's a rainy day here. I will start hunting down a new tranny cable until it clears up enough to raise the car and take a gander at the cable from the bottom at the tranny.

 

Generic OBD Error Code Details for P0706


Transmission Range Sensor Circuit Range/Performance


What does this mean?

OBD Code P0706refers to
The park/neutral position (PNP) switch includes a transmission range switch. The transmission range switch detects the selector lever position when the shift lever is in the N or P shift position and sends a signal to the Transmission Control Module (TCM).
Symptoms

Possible sumptoms of OBD code P0706
- Engine Light ON (or Service Engine Soon Warning Light)
Causes

Possible causes of OBD code P0706
- Open or short park/neutral position switch circuit - Poor park/neutral position switch circuit connection - Misadjusted park/neutral position switch - Park/neutral position switch may be faulty The Error code is generally activated on detection of the following conditions: The transmission range switch detects the selector lever position and sends a signal to the TCM.
Possible Solutions

 

the XK has been performing excellent until last Friday. I took the car for a ride and parked it while I went to THD to buy a few things. When I came back and started the car, the engine light got on and the message "gearbox fault" appeared. I droved the car home but performance was restricted, did not changed gears. Putting the OBD got a code PO706 "transmission range, sensor cicuit range/performance". I hadn't drive the XK since. Any thoughts??? By the way, is a 97 XK8.

Thanks.

 

Pull the shifter surround cover then visually inspect alignment of the 2 micro switches that are normally closed until the shifter stalk triggers them(opens the circuit) while shifting from park to neutral on to drive. If the neutral switch doesn't open then close while shifting to D then you will experience issues.

Shift to manual 2nd then back and you will get the gearbox fault for sure.
The D to 4th gear manual limit switch is normally open then closes when you select manual shift mode.

Also check all connections for corrosion especially then one on leading to the transmission. You have to pull the wipers, cowl trim and plastic firewall pieces to get to the connection center under the throttle body on top of the bell housing. While there, go ahead and inspect the PCM and TCM compartment for water intrusion or connector corrosion (right side of rear engine compartment). The top cover is a 2 piece design with a questionable seal begging for water intrusion. Mine has another hole and small cooling fan that vents into the right front floorboard. So if you have damp carpet look there!


I'm looking for the switches at electronics distributors as we speak because my neutral micro switch failed causing the same issue. I'll post when found for 5 bucks instead of 50...

 

After 5 days sitting in the garage, I started the jag and took it to a ride and everything was working fine. Guess what happened has to do with the rain, as that day was raining a lot. In fact, is when the jag had taken the most of water since I owned it. Everything working fine since.