Does anyone have any idea?...I have a V reg 1999 XJ sport. Today I went to start it and on turning the ignition key it just kept turning over with the engine failsafe mode warning showing. I moved it into Neutral and turned the key and it fired up no problem. I repeated it a few times and it will still only start whilst in Neutral.

 

The linkage or switch in the lever control has a problem -- it's all interconnected. It's normally the module under the shifter. I'm not sure if the linkage is off and the trans does not agree with the shifter....... if the same will happen.

My guess would be if you have not does anything to the car -- its the module.

 

My first thought too, maybe the limit switch indicating 'park'?

 

That's my thought, also.

 

Just for giggles...went down to my workbench and pulled out the spare shift box I have. If you carefully (CAREFULLY) pull the knob, knob jam fitting off the shaft, release the 4 screws holding the j-gate, you can see the microswitch which is the park position switch.


The shift lever is in the Park (P) position, which depresses the microswitch.




With the lever in the P position, the switch, as indicated by an infinite resistance reading on the meter, indicates that the switch, when engaged, is open.


when the shift lever is moved (CAREFULLY so as to NOT bung up the tabs on the microswitch), the park microswitch releases.


And the park position microswitch shows a dead short, which indicates that the switch is passing a signal to the ECM

Note, I didn't try the N switch to see what the logic was on that, but going to assume that it's a IF P OR N is selected (LOW), then the ECM will acknowledge the start signal from the ignition switch. If the ECM sees a NOT P OR N, then the car won't start.

Just my quick logic derivation...open to refinement.

 

I just solved this exact issue - with mine the shifter cable was binding and not letting the position sensor know it's in park, but neutral worked fine always. The park position is very exact, a difference in the cable of a couple millimeters is enough to throw it. I changed the cable and it is perfect now always, plus the lever moves MUCH smoother now, like new.

 

Oh, the way to identify if it is misaligned in the park position is if the P on the JGate does not light up red-color when in the P-position (stays white or has no light due to your backlight burning out) - if you have the same issue that I did, if you can get it to light up (jiggling the shifter) then the car will start in Park.