Auto gearbox reprogramming

[alphagemini]

I am informed that when the automatic gearbox fluid is changed at 40000 miles on a C class it is best to reprogram the gearbox ECU. Mercedes do not do this when they service the box. The following text was sent to me by Mastertech who seem to know what they are doing:-

"In an automatic box the fluid is used to run the gearbox as well as lubricate it, for example the gearbox ECU will activate a solenoid and creates hydraulic pressure with the gearbox fluid to select the next gear band, it's more or a hydraulic setup rather than "engine oil lubrication", as the gearbox oil degrades the oil picks up contaminants, burns etc... this slows the gear change process down and the gearbox ECU adapts over time as the fluid "ages", the gearbox ECU does not know when the old oil has been changed for fresh, so all the "adaptations" needs to be reprogrammed to zero otherwise it tries to run based on the old worn gearbox and new oil with old programming/adaptations can make extremely hard gear changes, slipping torque converter etc."

Why don't Mercedes carry out this procedure? Dose anyone have experience of this? This is a repost from an earlier question I posted. I think it needed a new thread.

Thanks for any comment.

 

[whitenemesis]

Mercedes do reset the adaptions, so do good independents. Every atf change I've had done also had the adaptions reset. Part of the SOP.

 

[AltonAnt]

Mercedes do reset the adaptions, so do good independents. Every atf change I've had done also had the adaptions reset. Part of the SOP.

Is this the process you can do yourself by holding the accelerator down at key position 2?

 

[alphagemini]

Mercedes do reset the adaptions, so do good independents. Every atf change I've had done also had the adaptions reset. Part of the SOP.

I have had a long chat with the service people at Mercedes in Ashford and they are adamant that an ECU reset is not done and is not necessary. I asked them if they could do it if I asked and they said yes but that it would cost an extra 166.80. As this reset is included in the service carried out by Mastertech I think Mercedes have lost a customer!

 

[ToeKnee]

But it's not an ecu reset, it's an adaptations reset! Slightly different terms but probably vastly different to how mercedes interpret your instructions?

 

[whitenemesis]

Is this the process you can do yourself by holding the accelerator down at key position 2?

No, only possible using STAR.

 

[zipdip]

Well you are paying the bill so Mastertech seems to be the place to go.

 

[alphagemini]

But it's not an ecu reset, it's an adaptations reset! Slightly different terms but probably vastly different to how mercedes interpret your instructions?

So they do reset the ECU but they call it something else? I will ask if they employ Star, then we may assume they do know what they are doing. I wonder why they were incapable of explaining their processes. Still charge too much.

 

[alphagemini]

I have been back to MB and asked them if the use Star after fluid change. They say they only use it as a diagnostic tool but not for reset/reprogramming after fluid change. So we don't know what we are doing, bit like brexit!!!

 

[jon.english68]

Resetting adaption and TCM reflashing are completely different, after a transmission service, resetting the adaptions is all that is required, see info below on how to do that, reflashes are only done when a manufacturer recognises a fault that can be over come with different software.

Sent from my iPhone using Tapatalk

 

[Chrishazle]

Pretty certain mastertech have Star.

 

[alphagemini]

Pretty certain mastertech have Star.

Mastertech have Star. They also talk to you

Thanks for all the help.

 

[alphagemini]

Resetting adaption and TCM reflashing are completely different, after a transmission service, resetting the adaptions is all that is required, see info below on how to do that, reflashes are only done when a manufacturer recognises a fault that can be over come with different software.

Sent from my iPhone using Tapatalk

This sounds like a driving style reset. Mastertech say they use Star to reset some of the parameters, are you saying this is all nonsense?
Why would Mercedes charge 166 quid to do a reset with Star if the procedure you mention is all that is necessary. Please read the quote I made above to see what Mastertech say.

Thanks for your help

 

[187umkillass]

Why would Mercedes charge 166 quid to do a reset with Star if the procedure you mention is all that is necessary. Please read the quote I made above to see what Mastertech say.

Because they can tell you anything and without any knowledge you have to believe them sply as that. Same story with sealed for life tranny. It's all about money. Random Joe Doe to save money will try to go to Indy's garage just to save some comparing toain dealer. And main dealer took lesson from that and these days you've got more complicated cars and they can be repair with special tools etc. ITC cover up and its all about money.
Dont believe in anything they said personally I've got bad experience with so called Indy's garages because lack of knowledge.

For me tranny reset is a electronic reset which means it reset the TCU. It's should be enough without using a STAR.