I have had the scan done that shows all sorts of issues with
transmission, such as gear not shifting, comression not right etc. Can
provide spefic codes if someone has a suggestion. I am having
intermittent problem of gear not shifting to higher gear 'in the
mornings' and is especially is a pain when it just 'shifts' to neutral
on its own. If you change gears at that time, the gear lever shifts
but the car remains in neutral. If you turn the switch off and on, the
gears shift right and you can go for hundereds of miles without having
the same problem again during the day.
Lately I have noticed that the compression is low as well as the car
seems to be making a lot of effort to move, 'in the morning' only. I
showed it to a mechanic who was cleless, and could not reproduce the
problem on test drive. Does anyone has any ideas because I dont want
to be forced to change transmission when it just might be some other
proble/reason for this behaviour. Any suggestions are welcome. Thanks
Thanks for the quick response.
The codes that came up are follows:
110-RPM compression N2 to N3 implausible
116-TR oil temperature sensor start
135-Can communication disturbed
146-Inadmissible transmission ratio
147-Gear implausible or transmission slipping
Is your mechanic a Mercedes specialst or just a general mechanic?
Diagnosing an electronic 722.6xx transmission is best done on an MB Star
Diagnostics computer system. It can do a lot more diagnostics that can
narrow things down compared to a Snap On scanner or whatever.
Another idea is that you could be experiencing the somewhat common
transmission connector failure/leakage and the fluid has wicked up to the
harness to the tranmission control unit and is contaminating the
electronics. This problem is showing up quite a bit on the 722.6xx
transmissions now. If you catch it fast enough before the TCU gets fried,
you can save it.
I took it in to an MB specialist who replaced the connector plate in
transmission. The fluid level was also low, so he flushed and replaced
with the lectronic fluid you mention. The harness had no oil on it so
I suspecting that the plate may not have been the problem, just the
fluid level. I paid $650 for the job and walked away feeling that I
paid too much. I have my doubts if the plate was needed to be replaced
but oh well, atelast I am not having the problem anymore. Replaced the
gasket so that the fluid doesn't leak anymore. Mechanic told me that
the fluid was supposed to have lifetime life.but what can be done if
there is a leak. Should I go back to the same mechanic next time?
Thanks Tiger and all for quick response, you guys rock and know your
The MB tranny fluid is really a killer... I think youpaid around $28 a
quart. Take a look at your receipt. I think that is typical cost of this
kind of service. If he did the job right, then he is being good to you.
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