2003 C230 Transmission failure.....

Mar 5, 2016 | 06:03 PM

cgoodwin

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1988 560SEL, 2003 C230,

2003 C230 Transmission failure.....

Start vehicle and it will shift into PRND and you can run through 1234

After a minute or two it goes into neutral regardless of the gear position. At this point you can no longer run through 1234 but can still shift DNRP and the changes are reflected on the instrument console.

Shutting it off for a few minutes allows you to repeat the process but if you shut it off and restart right away it is just in neutral.

No codes present
Fluid level ok and does not smell burned
No odd noises
No previous symptoms
Examined plug and found it wet. Replaced socket and cleaned connector well.
Examined harness and TCM found both wet and cleaned thoroughly.

Any ideas on how to determine if the issue may be the connector plate or valve body???

Mar 8, 2016 | 12:44 PM

kessel

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Joined: Mar 2011

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From: SF Bay Area

2004 c 230K and 2014 SLK 250

These transmisions are bullet proof as far as mechanical end , with that said all electronics parts of it is there to protect mechanical end. So I'm willing to bet that you have TCM failure as you said it was wet with oil. I dont think cleaning it will help, because internal parts might shorted out, Another possibility is conductor plate ( this will throw code like P 0715 turbine speed sensor which is part of the plate) but not CEL . Another one is shift solenoids or valve body.

Mar 9, 2016 | 12:51 AM

cgoodwin

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1988 560SEL, 2003 C230,

OK the TCM was not wet at all, just the harness.

After replacing and cleaning the harness and plug there was no change.

I Removed the valve body and replaced the contactor plate as well as cleaning the pan and all parts I could reach and replacing the filter, gasket and fluid.

Trans engages for a minute or two then again disengages. There is a slight rumble but it is only really noticeable at idle.

I noticed that the dash indicator reflects the gear selected by the shifter and you can toggle through 4321 this is also reflected on the instrument display.

When the trans disengages, the display still reflects PRND but does not allow you to toggle between 4321. When looking at the trans on the scanner (Snap On Solus) when the trans has disengaged the scanner shows the selected gear but shows N for the actual gear for everything other than P, which shows P.

I have decided that the issue is likely the pump or carrier bearing, although it could be the valve body as well. A replacement valve body is over $700 and I have located a good low mileage used trans for $750 so that is the direction I think I am going...

Mar 9, 2016 | 03:14 PM

bibauporto

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Joined: Feb 2014

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C220 CDI W203006

Hello, I had a similar problem on my 2002 C220CDI.

Have you considered a defective gear shift module? I changed the part and had it reprogrammed and it worked for me (I also had no error codes).

Cheers

Last edited by bibauporto; Mar 9, 2016 at 03:41 PM.

Mar 9, 2016 | 07:24 PM

cgoodwin

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1988 560SEL, 2003 C230,

Interesting, can you further describe your symptoms. I had considered the module but since i was able to communicate via the scanner I abandoned that possibility. I wonder if there is a way to test the module???

Mar 10, 2016 | 03:43 PM

bibauporto

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Joined: Feb 2014

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C220 CDI W203006

Quote:

Originally Posted by cgoodwin

If I remember correctly, the first symptoms were unable to change gears manually (only D, not 1234) followed by no gear changes (wouldn't go over 2nd or 3rd gear for example). Restarting the car would work for a while. Finally the car started to go into limp mode with gear lever locked in P position (having to manually unlock the lever and with first gear only).

Cheers