View Full Version : TCM reset
catch-22
4th March 2016, 04:31 PM
I was told from a dealer that in order to properly reset the TCM on my D4 that the diagnostics equipment had to be connected to the car whilst driven for one hour and that I was going to have to be charged an hour for someone to drive it.
Sounds odd to me.
Is this the dealer being difficult or is there some truth in this?
Graeme
4th March 2016, 05:37 PM
Most people just clear the adaptions using diagnostics then over time allow the gearbox to re-learn. However to do the job properly a sequence of short accelerations is required, going up 1 gear at a time before stopping and starting again then repeating the whole process multiple times. I have the documented procedure somewhere - I did it in my D4 after its rebuilt gearbox box was refitted.
catch-22
4th March 2016, 06:04 PM
Well there ya go....maybe I should learn to trust my dealer more..
LandyAndy
4th March 2016, 07:12 PM
Try using sport for a few days then return to normality.
The vehicle will adapt/re-learn.
Is there an issue you want fixed that requires the re-set???
Andrew
catch-22
4th March 2016, 07:16 PM
Andrew,
Good question, and yes there is. I towed my camper without a LED load resister meaning the car didn't know it was there. I've since got the parts to make the load resister and am not going to tow the camper until I assemble it. Since decoupling the camper (2tonne), the gears when slowing down feel a little harsh (actually that's not the right word....they change back a little early making it feel like a sports car)
I was thinking that with a reset that will that.
Dealer said it doesn't matter if the car detects a camper or not it will learn as it goes whereas I've read that the Tcm map changes when it detects a load.
Caine
Graeme
4th March 2016, 07:20 PM
I would let it sort itself out - it wont take long.
Meken
4th March 2016, 08:32 PM
Whack it in sport drive it like you stole it for a week then switch back to D ? If you can [emoji48]
LandyAndy
4th March 2016, 08:48 PM
Caine.
Dont worry about it,it will sort itself out;););););).
I got a near new D4 as a loaner,it went like a dog shot up the arse,despite being exactly the same spec as mine.
By the end of the day I had trained it to drive how I do,ie like an old fart.
Andrew
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