C250td Wont change out of first

[brynton]

Mornign all,
My 97 c250 td will only select 1st when put into D (acompanied by a jerk), you can get reverse and neutral but in D it just goes to the red line and wont change up even if you try manually moving it.

I have a new filter, oil and gasket coming this afternoon so I will be installing this.

There is plenty oil in the box, and it has 101K miles.

I have done quite a bit of searching on this site and noticed alot of people mentioning gettting the codes read on a star machine, Is this a generic analysys machine or a merc specific??

I really dont fancy driving the car anywere due to having to rev the plums off the old girl.

If its worst case senario, are all W202 boxes the same or will i need a TD spec version.

Many thanks in advance

 

[Dieselman]

You need the codes read, it's stuck in limp home mode.
It's unlikely to need a cpomplete gearbox, more likely a speed sensor or the electronic plate, but if required the box will need to be a 250TD box as they are built specifically to match the engine.

 

[brynton]

Thanks dieselman,

the speed sensors, I assume these are located on the box, are these easily accessable??

A friend has diagnostic machine but is 10 miles away. I may just tow it over.

Is there any way to reset without the codes being read, I read about hot cold cycles but is there possibly anything else???

Thanks again

 

[BlackC55]

The speed sensors are not easily acessable and should only be done by someone competant as it has to be done right.

 

[Dieselman]

I would guess it's stuck in 2nd as that is the default gear for limp home mode.
Just drive it to get the codes read.

 

[brynton]

Thanks blackc55 ,I was a mechanic and fitter in my early days so I have confidence and facilities to tackle it.

Is the sensor on the top of the box under the tunnel or somewhere a bit more practical.

I suppose what i am asking is it a box out job for either the sensor or plate as diesel man suggested??

Cheers

 

[BlackC55]

You have to remove the valve body and it is located on top of it. When you order the part ask for an electrical plate.