Speedo drive

Can anybody tell me if the sensor/drive mechanism is easy to access I found it on the CD rom well the drive in the gear box but no explanation as to where on the overall picture if its there I am probably blind!?
Problem being its not working, (now there`s a thing) - well its intermittent so its an annoying me.

[Mike M]

Originally Posted by pat

Can anybody tell me if the sensor/drive mechanism is easy to access I found it on the CD rom well the drive in the gear box but no explanation as to where on the overall picture if its there I am probably blind!?
Problem being its not working, (now there`s a thing) - well its intermittent so its an annoying me.

From underneath the car, rearside of engine it can be accessed. 10 minute job for any mechanic with a car lift. I would take it into a tyre type place and ask them to change it for you. It is an item which fails causing the speedo to either read wrong speed, no speed at all or intermittent speeds. This is for 3 litre 24v engine anyway

Hi Mike I don`t know if you are online or not but are you referring to the electrical sensor that fails or is it the drive that is inside the gearbox but can still be replaced once the sensor is off,I had similar trouble with my 155 when the plastic gear went and was a pig to get at?

[Mike M]

Originally Posted by pat

Hi Mike I don`t know if you are online or not but are you referring to the electrical sensor that fails or is it the drive that is inside the gearbox but can still be replaced once the sensor is off,I had similar trouble with my 155 when the plastic gear went and was a pig to get at?

Pat the speed sensor is a drive, they are one and the same (part number 7624310). The unit screws into the gearbox and then plugs into the loom (it looks and attaches just like a lambda sensor), when mine failed the drive inside the unit had broken and was spinning but not properly. Unbolt the unit from the gearbox and replace. It's a bit of a ***** to get to unless you can get good access from under the car and there is not alot of spanner room up in there so I ordered the part and then took mine to a local mechanic and he charged me a tenner to fit it for me.

yes I know its a drive Mike but what drives it according to to the gearbox breakdown at the point of diff description and associated parts you will see the sensor is driven by this nylon/plastic gear and this is the part I had to replace on the 155 and was no bundle of fun ,however I take your info as being very helpful and will try and establish what and where the culprit hides
Still no joy on the door lock front the unit I have found likening to the component seems to be different to the cd rom .What seems to operate the door locks is a double relay so I will try and get it checked----------and oh the code out/fault has still not been resolve because no one has turned up at my door as promised!!
Still I am having loads of fun in the blue 164!

[Mike M]

Originally Posted by pat

yes I know its a drive Mike but what drives it according to to the gearbox breakdown at the point of diff description and associated parts you will see the sensor is driven by this nylon/plastic gear and this is the part I had to replace on the 155 and was no bundle of fun ,however I take your info as being very helpful and will try and establish what and where the culprit hides
Still no joy on the door lock front the unit I have found likening to the component seems to be different to the cd rom .What seems to operate the door locks is a double relay so I will try and get it checked----------and oh the code out/fault has still not been resolve because no one has turned up at my door as promised!!
Still I am having loads of fun in the blue 164!

Oh I see, I have never heard of anything but the sensor itself breaking (I have had 2 164's and they both broke), haven't got a clue about gearbox internals.

Originally Posted by Mike M

Oh I see, I have never heard of anything but the sensor itself breaking (I have had 2 164's and they both broke), haven't got a clue about gearbox internals.

Its not too frightening just awkward to get at,the sensor screws onto a steal sheath which inturn holds a nylon spindle in placenext to the diff crown wheel once you release a grub screw the whole thing lifts out it doesn`t cost much thankfully but I will see what is wrong with mine hopefully its what you suggested Cheers Pat

[Mike M]

How did you get on?

PS: I PM'd you about CODE system on your car.

Mike

I forgot to update the speedo story,in the end the intermittant and subsequent failure of the speedo was the nylon spindle that is driven by the diff and drives the sensor a real ***** to change if you are lying on the floor!