Jedimerc

Hi All,
I've just bought a 2003 clk270 diesel Auto. It had been parked for some time and the wheels had ceased up. I put it in drive and accelerated & then in reverse and accelerated a few times and the wheels freed up. The brakes worked fine. I drove it to the garage for its MOT test with no problems. The mechanic called me later to say the gearbox is dead, it doesn't drive. He dropped the car off to my house and the following day. I tried to drive it, put it in reverse that was fine. Then in drive & that also was fine. I drove backward & forward a few times then nothing... no transmission? and I couldn't accelerate above 1000 revs? Is the car in limp mode or could it be something else???

I read a post....
1. Turn the ignition key to the on (not start) position.
2. Press the gas pedal to the floor and hold for five seconds.
3. Turn the key to the "off" position (don't remove the key), then release the gas pedal.
4. Wait at least two minutes for ECU to reset.

I tried this but it didn't work.

I read this post....
You could try disconnecting the battery for 10 mins, this sometimes works with soft fault codes.

Again this didn't work

The strange thing is when I leave the car off for a short while and then turn it on and drive it, its fine for a short while. Then it goes to no transmission and you cant rev over 1000.

I'm really desperate now, Any advise is appreciated.

Thank you!

Glyn M Ruck

That so called ECU reset is nonsense. It is, in fact, a throttle reset. All it does is synchronise pedal with throttle plate.

First things & then report.

- Check fluid level.
- Check electrohydraulic bush where TCU plugs into the RHS front diagonal of the transmission for leaks
- Lift the passenger side kick plate carpet ~ this will expose an aluminium kick plate to which the TCU is mounted. Undo fasteners & check the harness & floor for fluid that might have wicked up from the leaking bush.

The car is triggering limp. Sooner or later we are going to have to read stored codes.

Jedimerc

Hi
Thank you for your reply.

What fluid levels are you referring too?

I'm going to try and remove the carpet in the foot well and take a look at the TCU.
I have asked my mechanic to come and read the fault codes. If he cant do it the Mercedes have given me a quote for £150 to come and diagnose the problem.

Glyn M Ruck

The transmission fluid level. Take the pan temperature & check level with a service dipstick. You will have to buy a dipstick or take it to a dealer or Indy that has one. Then take the lock pin out of the the transmission tube cover & remove the cover. Push the dipstick down the tube until it hits bottom & take a reading.

Remember to check the electrohydraulic bush under the car. It is a stupid $10 part that leaks. Easy to replace. When fluid gets into the electrics the transmission will often go into limp mode.

If you want to make up your own dipstick here are the measurements.