Auto Gearbox Fault

[bedminsterbob]

Hi Everyone.
Over the last month I have had an intermittent fault with the auto gearbox, as I put the car into gear reverse or driver it engages with a clunk and a jolt and the gearbox fault light comes on. I just have to switch the car off and start it again and it works ok with no warning light. Any suggestion on what it could be ????

[Swiftly]

Don't have an auto, but have you checked if there are any error codes stored? It might be a good place to possibly start.

[bedminsterbob]

I have a cheap code reader, and it does not show any stored, I know the reader works as it always showed the codes on my xj8.

[Swiftly]

First the obvious, check the transmission oil level and condition. Has the oil and filter been changed recently?

Otherwise it sounds like it may be an internal problem. But without codes and frequency of the event you are guessing. It still may be a switching problem or even a problem with the ECU as it's like a command center communicating with the transmission module and modules setting engine parameters.

Hopefully someone else might have another suggestion or theory to help you