Hello everyone,
My newest toy is still playing up, i still get the gearbox overheat warning, it can light up as soon as i turn ignition on with engine stone cold or it might come on after 5 minutes or 3/4 hour then it will turn off . so connected solus up and checked readings , with cold engine i get engine temp say 20 but gearbox will say 32 or something. with car up to temp there is still a discrepancy between the two eg engine 96 gearbox 107. Then i noticed that the live data says engine rpm is eg 2300 when the gearbox rpm is showing 1500 but the tick over is the normal 6/700 the values do change when i rev the motor. Now would i be right in thinking that the TCM is having a tizzy fit and is not sure what it is reading (gearchange appears to be ok) if that is case (tried hard reset etc) would a reset with WDS help? next question if yes does anybody know how to do it.
Car still drives ok but would like to get a clean dash.
All best keep safe out there
rrosscoe

 

I worked at the dealer when these cars were new and this fault happened to a few X100 and X308 with the 5HP24.
Even cars that were only several months old had this same thing happen and Tech Line advised to replace the gearbox internal harness.

This fixed the problem.
The temp sensor is built into the harness.

 

Hi Motorcarman,
I am aware there is a common fault with the internal wiring but as this is an intermittent fault, and i still get readings on the solus with the fault flagged up on the dash can i not discount that one, surely if the harness is faulty then the codes and warnings would be more permanent even if there was a loose connection somewhere just making and breaking, just a thought.
as mentioned when first turned on with error showing overtemp when connected with solus i get a reading that is normally higher than the coolant temp but no where near what you would call high temp, eg engine showing say 21 and gbox showing 32 sounds like a bad/dirty connection to me what do you think?
rrosscoe

 

I have NO IDEA what the parameters are that trigger the OVERTEMP warning but we were advised to simply replace the harness under new car warranty and go on with our lives.

I did not use DATALOGGER to monitor the gearbox temp. The customer said the warning would come on with the engine cold on startup or sometimes driving on the highway.(bad batch of gearbox harnesses?)

I don't recall any DTCs so Tech-Line advised harness replacement. I described the customer complaint to Tech-Line, they advised replacement.
Every harness replacement cured the fault. I got paid and the customer was happy and went on their way.

I can't offer any more advise.

 

Thank you for your thoughts on it, have not started it for a while but have switched on ignition and at moment no warning lights or messages, will take it out and see what she tells me,think I will have look at the gearbox connector to see if it is contaminated with oil as i believe that is also a common complaint. will keep you postsed.
RRosscoe