Speedtronic issue - drive to workshop!

[Cheshire Boy]

Hi all - first post here but hoping someone can help.

I have a 2006 1.8l auto CLK convertible, 74K on clock, had for 15 months, no problems at all. No other problems.

Last month or so, been having issue with the speedtronic showing the error message in title of thread and as can be seen on image. It seems to happen when I pull the stalk down to decrease speed rather than when I first use it for cruise control or push up to increase speed, but it does not happen every time I do this.

Turning engine off and on again and all is OK. No problem with loss of power, no odd noises - car will drive as normal when error showing just can't use cruise control.

I have taken it to local (nonMB) garage and they have done a code read and can't find any cause (wasn't showing error message on dash at the time). I don't use the speed limiter function at all.

Anyone got any thoughts?

Cheers.

 

[kianok]

You need to get it plugged into STAR and diagnosed properly or you could be there forever trying to find the problem.

 

[l5foye]

Did you by any chance change tyres recently?

 

[Cheshire Boy]

You need to get it plugged into STAR and diagnosed properly or you could be there forever trying to find the problem.

Sorry for the ignorance - what is STAR? Is that something done at an MB dealer rather than a local garage??

 

[Cheshire Boy]

Did you by any chance change tyres recently?

I think it was a month or 2 before the issue started...what might the connection be?

 

[Smart320]

Star is the electronic system that plugs in and reads faults on the car. MB dealers and any MB Indi will have a Star system, which is set up specifically for Mercedes, your local garage will not ( their system might or might not be able to diagnose the fault ) save time and money by getting it checked on Star

 

[Cheshire Boy]

Star is the electronic system that plugs in and reads faults on the car. MB dealers and any MB Indi will have a Star system, which is set up specifically for Mercedes, your local garage will not ( their system might or might not be able to diagnose the fault ) save time and money by getting it checked on Star

Many thanks.

 

[DesmoFab]

Hello,

Since your last post, did you solve your problem ?

I have exactly the same thing with my clk. Everything works except when I want to decrease speed :/
I already checked errors via autocom and I got some error arround steering column but I don't know if there are a link between events !

 

[pavilionn]

Did you by any chance change tyres recently?

Greetings,

I have recently got into a similar situation with the speedtronic issue. Before this the ABS/ESP faulted as well.

These issues appeared a few days after I changed the tyres.

Do you have any information regarding the connection between the tyres and the errors?

 

[johnsco]

It's possible that one of the ABS sensors (or its cable) has been damaged when jacking up to change the tyres.
Quite a lot of the engine management functions rely on the signals from the ABS sensors.
Plugging the car into STAR is the surest way of sorting these types of faults.

 

[pavilionn]

It's possible that one of the ABS sensors (or its cable) has been damaged when jacking up to change the tyres.
Quite a lot of the engine management functions rely on the signals from the ABS sensors.
Plugging the car into STAR is the surest way of sorting these types of faults.

Thank you. I will keep the topic updated with new informations regarding this issue.

 

[219]

Greetings,

I have recently got into a similar situation with the speedtronic issue. Before this the ABS/ESP faulted as well.

These issues appeared a few days after I changed the tyres.

Do you have any information regarding the connection between the tyres and the errors?

If you only change tyres on one axle ( or indeed any combination where you end up with new/part worn tyres ; or a mix of different brands of tyre ) then you can end up with different circumferences on different wheels . While this might not seem significant , the sensors can pick up very slight differences in rotational speed from one wheel to another , and this can sometimes cause the issues you are experiencing .

 

[johnsco]

For similar reasons, check your tyre pressures.
Again, this can cause slight differences in rotational speed and cause the ABS sensors to provide inconsistent inputs to the EMS

 

[pavilionn]

Still checking on it. The ABS/ESP are still deactivated. Soon I will check the issue at the workshop.

Thank you @johnsco and @Pontoneer for
the replies.

Actually I have changed only the rims and set the same tyres used before. Same brand, different dimensions (205/45/r17 - front axel) (245/50/r17 -back axel)
There was no problem with these tyres and the old rims.

Basically the geometry is still the same. The only difference is that the new installed rims have a slightly smaller ET.

I’ll keep you in touch.

 

[pavilionn]

If this is the case, is there any sensor calibration that needs to be done?

 

[Bobby Dazzler]

Still checking on it. The ABS/ESP are still deactivated. Soon I will check the issue at the workshop.

Thank you @johnsco and @Pontoneer for
the replies.

Actually I have changed only the rims and set the same tyres used before. Same brand, different dimensions (205/45/r17 - front axel) (245/50/r17 -back axel)
There was no problem with these tyres and the old rims.

Basically the geometry is still the same. The only difference is that the new installed rims have a slightly smaller ET.

I’ll keep you in touch.

How wide are the new wheels (eg 8.5j) and what is the offset (eg ET37), and are the wheels the same size at the front and rear?

How wide are the new wheels (eg 8.5j) and what is the offset (eg ET32), and are the wheels the same size at the front and rear?

Are the wider tyres mounted on the wider wheels at the rear of the car, and likewise narrower wheels/tyres at the front?

Your tyres aren’t the standard sizes and so the issue could be caused by the differences in rolling radius confusing the cars systems.

For a 17-inch wheel the tyres should be 225/45 (on 7.5j wheels) at the front and 245/40 (In 8.5j) at the rear.

Even if the tyres are the very same as before, if the new wheels are a different width then it will stretch the tyre differently, which could push the rolling radius even further from from what the car’s systems expect, causing the issue you’re experiencing.

 

[Bobby Dazzler]

How wide are the new wheels (eg 8.5j) and what is the offset (eg ET37), and are the wheels the same size at the front and rear?

How wide are the new wheels (eg 8.5j) and what is the offset (eg ET32), and are the wheels the same size at the front and rear?

Are the wider tyres mounted on the wider wheels at the rear of the car, and likewise narrower wheels/tyres at the front?

Your tyres aren’t the standard sizes and so the issue could be caused by the differences in rolling radius confusing the cars systems.

For a 17-inch wheel the tyres should be 225/45 (on 7.5j wheels) at the front and 245/40 (In 8.5j) at the rear.

Even if the tyres are the very same as before, if the new wheels are a different width then it will stretch the tyre differently, which could push the rolling radius even further from from what the car’s systems expect, causing the issue you’re experiencing.

I asked how big are the new wheels twice! The second time I was intending to ask about the old wheels!

 

[pavilionn]

The offset (ET) is the only parameter that has changed. I don’t know the exact values but the new installed rims have a smaller offset that is for sure.

 

[Bobby Dazzler]

The offset (ET) is the only parameter that has changed. I don’t know the exact values but the new installed rims have a smaller offset that is for sure.

Are the wheels different sizes, front compared to back? If so, are the wider tyres fitted to the wider wheels, and fitted on the rear axle?

 

[pavilionn]

Are the wheels different sizes, front compared to back? If so, are the wider tyres fitted to the wider wheels, and fitted on the rear axle?

Yes. I have installed the HOEDUS model on a w209 model.
Front 7.5Jx17 ET 34 + 12mm spacer
Rear 8.5JX17 ET36 + 15mm spacer