SL R129 gearbox problem

[Les]

My SL60 R129 gearbox for the second time this year has refused to change gear above first.
Been sent to local mercedes specialist both times and he has reset the electronics which has cured it.
It seems to happen after the car has sat for a couple of weeks (I leave it with a battery conditioner/charger connected).
I've been told permanent fix is to replace electrical plate in gearbox. at £xxhundreds or keep coming back for a reset.
Question has anybody else had a similair problem and have a fix.
Can I reset the electronics myself if it happens again? Is there a special tool needed.

Les

 

[BlackC55]

The electrical plate is only about £450 fitted. I would do this as it will only get worse if that is the cause of the problem.

 

[BTB 500]

Electrical plate is a common issue and relatively cheap to fix - I paid £370 in total to have mine done, six years ago. It had gradually got worse over a period of about a year before that.

 

[230K]

I had to replace the electric plate on mine too. Not too difficult to do if your handy with the spanners. Replace the pilot bushing when you are at it together with the filter and give it a fresh fill of oil.

Out of interest on mine it seemed to be the spring on the speed sensor had gone weak. Is this the problem or do the electrics to the sensor break down.

Anyone???

230k

Sent from my GT-I9505 using MBClub UK

 

[axelvic]

I've replace two conductor plates in 722.6-boxes. The job is quite straight forward and rewarding. The first one on an '06 E200 CDI (ex-taxi) had visible cracks in the speed sensor, the other one in an '01 E320 CDI showed no signs of wear or tear at all.

Both cars were stuck in second gear due to this.

 

[dinoy]

surely this is not sl60 special and u can buy any w129 gearbox and nab the part to replace yours, of course it is always better to get new part installed

 

[BlackC55]

The part is about £270 now.

 

[Les]

Thanks for replies.
Looks like next time it happns I should replace the plate in the gearbox. The local merc specialist has quoted approx £600 which is not too far away from your indicative costs.