Hi all, as the title states me 98 xj classic is throwing codes P0758 code and is in limp mode

done a little reading on this. Looks like my best route to diagnose the issue is looking for bad grounds as I believe the tcm and cps share a ground. I’ve already cleaned off the ground on the dipstick and planning to go around the rest to give a good cleaning in case.

what are your suggestions for other causes??

shift solenoid b is relatively new and I’d rather not go digging around those if I don’t have to. Could it be a case of just a bad cps?

edit: car still starts no problem, and drives. Just stuck in one gear (either 3rd or 4th if I had to guess)

Edit 2: trans fluid is a good colour, not burnt and topped up



update: someone told me a bad tps can cause similar issues apparently??? Tested my tpu, output was good at 5v but tested the sensor wire which should go up to 4.5 volts. Only went to 3.5v.

question is, could this really be the issue or just another thing to fix?