Fantomas

Was driving along @ 25mph and hit the kickdown switch, car took off for a split second and then just jumped out of gear, like I had put it in neutral. Tried a few things, shifted from comfort to sport and it revved freely, then to manual, the display was showing M4 but still no forward movement while revving like it's in neutral. Shifted between N and D, cluster was registering the gears but nothing changed. Tried shutting it off while rolling in N and restarted the engine, still got nothing. I found a safe spot to pull off, put it in P and shut it off. Restarted it 30 seconds later, ran and drove fine since then. Ran it through the gears @ WOT and nothing unusual.

Ran the codes and the engine stored P2069 (saying theres a code in the transmission module) and the transmission has P2500 (transmission has impermissible gear ratio). Checked the freeze frame data in the transmission computer, current gear is 3 and target gear is "shift aborted". Something caused the transmission to totally **** the bed during a 3-2 shift. Car has 71k miles on it, owned it since 66k, first time this happened, I'm anticipating it will happen again in the near future.

Been doing a lot of searching here and have the following thoughts:

1) Probably not the conductor plate, that issue has a few p07xx codes to go along with it and also transmission just going into limp mode, 2nd gear only, I lost all drive.
2) Could be oil in the 13 pin transmission plug, again this issue usually just puts you into 2nd gear
3) Probably not the valve body or solenoids, car still drives in limp mode
4) Most likely culprit: Leaking front pump, found a few posts that refer to this symptom and this issue, car pops out of gear, restarting fixes the issue. This thread talks about it on the E55, I had exact same symptoms: https://mbworld.org/forums/w211-amg/...nny-issue.html

A lot of info in this thread:
https://mbworld.org/forums/clk-class...-out-gear.html

I'll drive it again tomorrow and bring my scan tool along in case I run into any issues.

Has anybody dealt with this issue?

Zabe

Hi mate,

Did you ever get to the bottom of this, if yes what was the resolution.

Many thanks

insame1

I had a similar issue that was very intermittent. It was in fact a cracked sensor on the conductor plate.

Zabe

I'm doing a full gearbox service on Saturday with a conductor plate, so I hope my car will be perfect again.

Fantomas

Car has 85k miles now, hasn't happened since.

Zabe

What was the issue with yours.

Lukas Valek

Hi guys,

My C-class 2003, w203 dropped out of gear several times last half year in different situations. Most of times transmission just kicked out the gear after I quickly release gas pedal during acceleration. Symptoms are almost same like described above, however in my case, all needed is to slow down to maybe 20 30 Km/h and transmission suddenly find a gear. Once also happened while driving down the hill without gas pedal, the car was accelerating and without any action it kicked the gear. Worst occurence was when it got stuck in 2nd gear and cluster didnt recognize even R or manual shifting in D, this time only restart helped.

I brought the car to original MB service, found codes P2500 & P2502, they were shocked by missing oil in transmission after last service (february 2019), it was missing 0.5 l of oil, however they didnt find any leaks.
By the way, these issues were followed by unstable revs of engine on easy/slight gas pedal. Revs were oscilating for example between 1400 - 1500 RPM with significiant feel that car is speeding up and down. Gas pedal on the floor was totally fine.

Thank you for sharing your resolutions !

Mark Oldfield

I had the same issue this week, twice on one evening. Jumped out of gear and wouldn't reset. The W/S button and manual selection wouldn't work either... I stopped and turned the car off... and on again... All fine... until it refused to change up... stayed in 1st or 2nd gear!!!, So it is an electronic problem.. I happened to come across a YouTube video from a guy called Scotty (American very good mechanic) he was telling of several of his customers having problems with auto boxes, power windows and ecu's throwing wobblies!!! It turned out to be emf radio interference coming from cheap USB adaptors (no emf shielding in the design) He unplugged the adaptors and everything worked fine. I have one of these radio SD transmitter adaptors that I got from China cheap and it is plugged in directly about the auto box!!!! I have unplugged it, and straight away, the gearshifts seemed more positive, It might be in my mind... but, you never know? I am sure it's not an ATF oil issue as I replaced it and filter just 3000km ago.
I also had a turbo problem on the same evening... lost all boost!!! No check engine warnings..I stopped, turned ignition off, then on again... All ok 🤔. I don't think the two faults are related, as yesterday I found severely perished 8mm dia vacuum hoses on the LHS just next to the expansion tank plugged into a control valve... I believe they were collapsing under vacuum. This weekend I am replacing all the small diameter vacuum hoses! I am sure this is the issue as I had the same fault on my old 2001 BMW e46 320d.... replace perished vacuum hoses and the car had around 20% more power (The turbo was being controlled properly). Time will tell whether the auto box problem was being caused by RF interference... I know a bit about electronics, so I can see it might cause this and especially as it looked like the transmission computer totally crashed.... Yes, it did log a Fault code P2500. (icarscan MB2 reader).

perished vacuum hoses