johncan

Hey guys, so recently I have (again) acquired a 2003 CLK55 (has 107k right now) that I used to own two years ago. Same exact car.

The problems are that its throwing two transmission related codes. P0715 and P0730. This was through an OBD scanner that I borrowed from NAPA. Also, I'm getting P0123 and P0221, and the Mercedes stealership diagnosed that as the throttle pedal position sensor, which I have purchased online and waiting for it to arrive. So, the latter could possibly fix the transmission problems.

The symptoms of the transmission are that when I accelerate hard (on a closed course, of course ) and quickly let go of the throttle the transmission will fall into limp mode (in neutral, can't shift modes, etc.). There was also some awkward shifting at times. Also, it seems as if the car doesn't want to downshift often. The throttle really needs to be pushed down (maybe halfway to 3/4 down) to get it to downshift in "C". When you start pushing the gas (not enough for it downshift), the revs start dropping (torque converter related?) quite a bit.


What has been done so far in my ownership, is the notorious "pilot bushing" leaking, so I replaced that while cleaning the the entire harness and removing the stupid cloth tape. Now, there was a little ATF on the connector to the TCU and I almost **** myself. However, I opened it up and there was no sign of ATF inside so I just cleaned it with electronic cleaner, then cleaned the other two connectors from the harness. I then put dielectric grease on it and reassembled. The transmission became much much smoother, and now hardly falls into limp mode. But it still does. I also discovered a service record that the transmission was changed at 60k miles under warranty.

So if you guys have any input, that would be appreciated. As far as future plans, I have a new pan gasket, filter and Fuchs oil on the way to flush the transmission. Yes, I have the dipstick tool. I have done a ton of research but it seems no one has had the same symptoms as me. Also my question is would the TPS be causing the transmission limp mode? I'm pretty clueless here, and I'm about to buy a
MB STAR C4 SD Connect Multiplexer with hard drive (from the US, lol, not China) so I can avoid $116 per hour diagnosing and I have used SDS and DAS back in the day. Any input is appreciated.

GTibunny8v

The P0715 fault is for an internal speed sensor in the transmission. The repair is to replace the electrical plate on top of the valve body. The P0730 is implausible gear ratio which can be caused by low trans fluid or a mechanical slip inside the trans.

johncan

So weird... Couple days after cleaning the TCU, it seems like all of the transmission symptoms went away. Doesn't fall into limp mode at all anymore. The fluid level was good. Still going to flush it though. Added maybe half a liter of ATF. Still have to clear the codes and check again. And by the electrical plate you mean the conductor plate? I'll hold off on that until another code comes up or something.

shahabfaiq184

Hi guys last week I parked my MB C200 Kompressor car outside home and one again started it says transmission visit workshop but after some it worked finally and then this message was coming on and off now while driving it says transmission visit workshop and select gear again. Can someone please help me.

johncan

Well, just so you know I replaced the accelerator pedal position sensor and all the symptoms disappeared. No more codes or limp mode. And shahabfaiq184, please read the codes with a code reader or have the dealer diagnose it and post the results here so we can better help you.