(c-class) Speedo And Mileage Counter Not Working

[tonyc]

I purchased a 1994 C-Class Merecedes C200 Elegance this afternoon, only to realise that the Speedo and also the mileage counter is not working.


Please could someone advise me what the problem could be and also how I can try to diagnose and resolve it.


Thanks


Tony

 

[mapleleaf]

BEst bet is take it back to the seller! sounds a bit iffy to me . Is that an MOT failure item? How can you be sure of the cars true mileage? Mind you, its relative to how much you paid I guess. Sorry I cant offer any tech help on this , but someone here will I am sure.

 

[PJH]

At best it sounds like a loose cable (why) at worst it's been clocked.
As Steve_bcs says, take it back to the seller.

 

[IanT]

Sounds to me like the wheel speed sensor is either faulty or disconnected. Does the ABS light work, and is it on?

Ian.

 

[tonyc]

The car was purchased with a FSH. It also had a MOT done in December 2003 with a mileage of approx 53K and it is currently stuck on 55K. The speedometer isnt working and also the digital mileage counter. Also the ABS light is constantly on.

Further advise would be appreciated.

 

[IanT]

We've spoken by MSN.

I suggested checking the wheel sensor looms from the front hubs back to the chassis, then the connections where they plug in near the suspension mounts.

IIRC the sensors are used for both ABS and speedo / odometer, but also for the radio on pin A1. The ABS light being on is probably a good sign in that Tony is probably looking at a single failed wheel sensor or connection.

Ian.

 

[IanT]

Just thought... does the speedo suddenly work at an extreme of steering lock?

Ian.

 

[IanT]

OK...

I've been talking to Tony some more.

He's been to an Independent who thinks the cluster is probably faulty and quoted £240 plus £60 labour (plus vat) to replace the speedo cluster.

I don't know what tests they have done but it doesn't sound like they diagnosed the ABS light as a fault and were hoping that replacing the instrument cluster would solve it. I'm doubtful and have suggested that Tony checks his ABS for faults BEFORE going further with the dash replacement idea.

So, I have some questions:

1) Is the ABS disabled (as on Vauxhalls) when the dash telltale is on?
2) Where are the connections for the wheel sensors to the ABS (so Tony can check the signals)?
3) Is the radio loom in the W202 connected to the speed pulse line (giving a nice easy way of checking it)?
4) Is there any kind of blink test available on Merc ABS (Isn't it Bosch?) that's accessible by connecting a wire link somewhere in the diagnostic connector, and flashing numeric codes out on the ABS warning light?
5) Which wheel sensor does the ABS use to supply the speed sensor to the speedometer?

Failing that... doesn anyone see any logic in the diagnosis offered by the garage? I don't think it holds water...

Cheers, Ian.

 

[stwat]

Take it back to the vender,FFS!!!!!!!!!!

 

[IanT]

I believe it was bought from auction and that the price was very favourable.

I doubt the auction would take it back now (too late) and he's otherwise very happy with the car. My gut feeling is that he is looking for a simple fault in the ABS that's causing the speedo not to work. It's certain that the mileage displayed is incorrect, but for now, fixing the ABS and speedo is the prevailing priority.

I think you have to reject a car within an hour of the sale (or something like that) if buying from Auction and they would no doubt point out that the ABS light would have been on at the time of the sale (as the car was driven through). I reckon we can collectively help Tony fix his car and save some money along the way.

Ian.

 

[IanT]

I've just found the eBay auction with a W202 instrument cluster up for grabs.

Much cheaper than the one offered by the garage (probably brand new) and I still don't think tht's the source of the problem. Here's the link anyway:

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&category=10398&item=2485319263&rd=1

Ian.

 

[pluggers]

Thats one of the face lift clusters which are slightly different on the rear,Will fit in but not sure if all the functions will work correctly in a pre facelift car.

 

[Shude]

Thats one of the face lift clusters which are slightly different on the rear,Will fit in but not sure if all the functions will work correctly in a pre facelift car.

The w202 instrument cluster went through 2 changes, there is a 1993-1995, 1995-1997 and 1997-2000. If you use a cluster from the wrong year, the speedo might work and maybe the fuel gauge, but little else. You need to get one from the correct era.

 

[IanT]

The w202 instrument cluster went through 2 changes, there is a 1993-1995, 1995-1997 and 1997-2000. If you use a cluster from the wrong year, the speedo might work and maybe the fuel gauge, but little else. You need to get one from the correct era.

Thanks Shude,

He's got the earliest one, so that eBay one would probably be no good I guess. Not to worry.

So, I have some questions:

1) Is the ABS disabled (as on Vauxhalls) when the dash telltale is on?
2) Where are the connections for the wheel sensors to the ABS (so Tony can check the signals)?
3) Is the radio loom in the W202 connected to the speed pulse line (giving a nice easy way of checking it)?
4) Is there any kind of blink test available on Merc ABS (Isn't it Bosch?) that's accessible by connecting a wire link somewhere in the diagnostic connector, and flashing numeric codes out on the ABS warning light?
5) Which wheel sensor does the ABS use to supply the speed sensor to the speedometer?

Does anyone know the information above, or have access to a copy of WIS that I could have a dig in?

Cheers, Ian.

 

[Britishbeagle]

Resolution?

Did this matter/problem ever get resolved as I have the same problem with my w202 c180.

 

[Britishbeagle]

Fixed!!!!

On another forum found the answer to the abs light on and speedo mileage counter not working! Replaced the 10 fuse next to the diagnostic input socket, the round one under the plastic cover and hey presto, light out and speedo etc all working, much relieved it wasn't a new sensor needed so try this first.

 

[birdalone]

teething troubles

On another forum found the answer to the abs light on and speedo mileage counter not working! Replaced the 10 fuse next to the diagnostic input socket, the round one under the plastic cover and hey presto, light out and speedo etc all working, much relieved it wasn't a new sensor needed so try this first.

Hello chaps- new to the forum and looking for advice already.I bought my first mercedes just the other day for very little money. It's a 1994 c200d owned by an old chap for the last 15 years but parked up in his garage for the last 2 years. I noticed when I viewed it that it had the faults as quoted by Britishbeagle and did a search online- found this solution so I didn't fret too much and bought it as it seemed sound otherwise. I am wondering now where exactly is this 10 fuse. Do you mean the number 10 in the fuse box under the bonnet? I cannot see a round diagnostic input socket under a plastic cover. As I said earlier I am a Mercedes virgin really- more used to old Volvos and Saabs. If anyone would be kind enough to help me out with locating said fuse please?

 

[Dec]

He may mean that it’s a 10amp fuse, it may be the fuse on the O.V.P. at White arrow in picture below.
The fuse chart below is of a 1994 C180 W202 Engine bay fuse box.

The round cap in the picture is the “diagnostic input socket”
I’m not sure exactly what fault is causing you problems?

Dec