phamine

I bought a 2001 C320 and had shifting issues with the car.

There would be a delayed shift from dead stop going through the first couple of gears. Once it hits highway speeds, there aren't any issues with shifting up or down.
The dealership stated that I needed a "transmission sensor" and the part alone would cost me $300.

Anyone know where this sensor is located or what the part number would be?

Glyn M Ruck

It's possible that they are talking about the turbine speed sensor. If so it's likely a conductor plate issue. Please post codes.

SunnyRayToronto

What the mileage on the car? Did it have transmission oil changed ever 39K miles (60K km)?

How did the dealer determine its the transmission (speed) sensors? Did they hook up the car to Mercedes-Benz STAR Diagnostic System? If so, you paid for it and you own the diagnostic report with the codes, so post codes.

The conductor plate has about 6 speed sensors and you can't just buy one speed sensor and pop it in, you have to buy the entire conductor plate,... best to get a Mercedes indy to do this transmission work.

But do yourself a favour, FIRST check your transmission pilot bushing adaptor to see if its leaking transmission fluid (search!),... chances are it is,.... and if enough transmission oil gets into this transmission pilot bushing adaptor or onto the TCU it could also mess up the reading from the transmission speed sensors,..... Unless your dealer did a thorough test with MB-STAR DAS and tested and checked each transmission solenoid and other parts, I think you should check your transmission pilot bushing adaptor and do a partial transmission oil change before messing with the transmission speed sensors on the conductor plates.

C230 Sport Coup

Sunny, I'm sure he has no idea what a pilot bushing is...
but this should help.
The orings go bad and leak into the transmission wiring harness.
http://www.installuniversity.com/mb/...ans_oring.html
Eventually they work there way to the TCU (transmission control unit)
and killing it, from getting soaked with oil, which btw is located under the carpet and floorboard of the passenger side.

And considering you have a 2001, you've probably never flushed the trans fluid.
That causes all kinds of mayhem, and of course the dealer will want to sell you something you may or may not need.
Not likely you can get a dealer to do a full flush, and many of us DIY to be sure it's done right. Most times you pay someone to flush your tranny all they do is nothing.

AND then there's the Valeo radiators that leak coolant into the transmission, search on that.
You'll want to check all of these things to get to a basepoint.
And yes, the codes!!!!

phamine

Here are the codes. Seems like every has 2 or more of the codes so it's common.
I used VAG software for generic codes.

Address 10 (Engine): 5 Faults Found:
P0600 - Powertrain Data Bus: Missing Messages
P0720 - Transmission Output Speed Sensor (G195): Circuit Malfunction
P0702 - Transm. Control Module Electrical Malf. (SAE) or Control Module Defective (VAG)
P0600 - Powertrain Data Bus: Missing Messages
P0705 - Transmission Range Sensor (F125): Circuit Malfunction

I changed the pilot bushing and refilled the trans with a little under 4L of ATF.
Just test drove it and "abused it" trying to replicate the issue I was having. So far so good.

SunnyRayToronto

I'm really don't know what a VAG is,.. or how to use it? (insert your own jokes here!)

Anways,...did you get those codes after you changed the pilot bushing and did the partial transmission oil change? If so, did you clear your old code?

Once you clear your old code on STAR, the transmission will recalibrate itself to your driving style based on your next 50km. It's really not neccessary to clear the codes.

I'm assuming you also checked for oil at your TCU under the front passenger foot plate,... should be bone dry without any trace of oil.

LILBENZ230

VW Auto Group.. lol

hahaitzmickey

#WHY WASN'T THIS A RECALL. .. .. ... I had to do this when I changed out that crappy Valeo Radiator. This list keeps growing so be prepared..

phamine

I spoke too soon. Issue is back.

Check out the video. The cluster becomes erratic and a bunch of malfunctions come up. I've seen 11 malfunctions at times.

So in the video, I was driving 60mph. Engine and shifting was fine. Anyone have any ideas on this cluster issue. I pulled the codes again and received the same codes.

http://www.youtube.com/watch?v=hpM4J...ature=youtu.be

samaritrey

sounds like my issue
https://mbworld.org/forums/5024133-post499.html

phamine

^^Very similar if not exact.

I'm going to take a look at that later this week.

Thanks

samaritrey

any updates?

craigzy212

I am suffering the same fate with my C220 CDI... In the past year its had a new alternator, battery and the transmission was services 13 months ago. Did the bush replacement work in the end? or did you get a new conductor plate for the sensor?

I also had a catestrophic ECU failure when accelerating one day - red screen, lost power immediately... restarted engine and fine. is this related? My garage have been great, so would i look at the ECU reprogramming first, or replace the parts for the error codes (same as this post)

Car has done 110k miles

BF_JC230

Stuff like this makes me glad I have to push my left leg and move my right hand to select a gear...

good luck all!