antesusic21

Let me start off by saying that this car has been sitting for a while with ripped airmatic line. It's been a year since I bought the car and just now got around fixing it. So, I installed two brand new Arnott air struts. The car now airs up and finally sits as high as it should. However, when I got the car, auxiliary battery was pretty bad, and it would not take a charge. The main battery wasn't the best either. I put a brand new aftermarket battery in the trunk and it gets good 14.5V when the car is started. Car starts just off of that battery. After I fixed the airmatic system, I thought I would get to drive the car. "Car too low, stop." message went away, but "Visit Workshop" message with a picture of a battery above it, was still there. I thought it was there only because of the auxiliary battery. I put a good small 12V battery to replace the auxiliary battery, and it gets 12.7V. This did not change anything, the Visit Workshop message still pops up and the car will not move at all.
Now, I assume my transmission is in "Limp Mode", especially since after the "sneaky reset", it will go in gear and move for about 5 seconds, when the message pops up and car stops moving.
I am almost at the point of taking the car to a certified shop to see why the limp mode will not go away, but I am scared they will hook their computer up and first thing they see will be a type of "replace the transmission", or "replace ECU" message even thought it is most probably something very stupid and cheap. Has anyone experienced something like this before?

F1Fan

12.7V seems low. I just replaced the aux battery a few weeks ago and the voltage was over 13V. You may want to inspect the voltage regulator to see if the alternator is charging properly.

bbirdwell

For information on the charging system, search on "K57/2 relay". Also bring up the voltage on the instrument cluster using the cluster buttons so you can monitor the voltage real-time.
https://mbworld.org/forums/w211-amg/...e-display.html

Transmission issue you need to place the car on a diagnostic system. Electrical fault will remain in limp mode until fault cleared with STAR after malfunctioning part repaired. Mechanical/hydraulic issue will go into limp mode but fault will clear after key off/on cycle. Transmission will then function as designed until the mechanical/hydraulic fault reoccurs. Put it on a diagnostic system and verify the adapter plate solenoids, read out the transmission clutch/brake pack adaptation values, measure the fill pressure, and determine the fill and switch times. Your sneaky reset removed the adaptations performed by the TCU that were made to account for wear in the clutch/brake packs.
https://mbworld.org/forums/w211-amg/...rmination.html