W220 Gearbox Troubleshooting 722.6

[Ihl82]

I am looking for a transmission fault on a vehicle with no known history other than "transmission was replaced".
The vehicle is an S350 W220 with a 722.6 transmission.
The car does not shift above 2nd gear.

ETC stores two fault codes:

P2563 The gear is implausible or the transmission is slipping (4th gear).
P2562 The gear is implausible or the transmission is slipping (3d gear).

I noticed that I can't access the ESM module and the target/actual gear status is not consistent for each gear. Shouldn't a fault code be generated in the ETC module if the ESM is faulty? I checked the adaptation data and the values for all gears were within tolerance. After that I tried clearing the adaptations, but it didn't help. The car still won't shift above 2nd gear.

I would appreciate any advice or recommendations for further troubleshooting.

 

[GIN]

You need to check if the gearbox is actually installed correctly (check 722.644 by VIN) and of course you need to check if there is power to the ESM, CAN and the diagnostic cable between ESM and OBD is not damaged.

 

[boonyen]

I had this situation before, I tried to change the transmission control unit, but without success, in the end I found that the coding does not allow me to change gears, you can try to read the coding of another similar car model and try to change it on yours. Hope this helps.

 

[GIN]

To do this you need to determine what gearbox is installed (722.6), see what coding is in the TCU, know exactly what gear ratio the rear axle has, based on this information you can adjust the coding line or find the correct coding for the gearbox and program it.

 

[Ihl82]

I will find out if the correct transmission is installed. I think I need to visually confirm this with a sticker or number on the casting.
Is it possible to find out the actual coding and gear ratios of the rear axle using Xentry/DAS?
ESM and ETC seem to interact. Actual gear status is displayed correctly in P and N positions.
Could it be that in some models the ESM is accessed via ETC? I think I read about this in some forum thread.

 

[GIN]

The rear axle ratio can be found in the EPC by VIN, the gearbox code is indicated on the housing, the actual gearbox coding can be found in the DAS developer.

 

[Galahead]

I had the same problem, it turned out to be a problem with variant coding.

 

[bigchevy66]

The EPC will list the factory rear gear ratio, but there is a flat machined plate on the rear differential housing, usually near the differential cover, that also lists the ratio.