Sipstrassi

Hi guys
I have a visit workshop light on my wife's CLK.
The external lights and the dash lights go out for a few seconds and come back on and now the doors are unlocking and locking all by themselves as you are driving and the seat belt assists are extending.

I have replaced to battery - light still on.
I was told it could be the voltage regulator on the alternator
- new voltage regulator.
I have replaced the alternator.
I have checked the voltage
- 12.9v engine off
- 14.4v engine on
- 13.5v with all lights on, air con on, front and rear window heaters on.

So I assume the charging system is working.

What do I need to check/change to get rid of the Visit Workshop light?

Cheers
Sipstrassi.

Plutoe

Hey Biff, you still have not diagnosed the fault---spend some money on the diagnostics before you go crazy and waste all that money on parts!!

PS: Understand your limitations!!

Sipstrassi

Had it hooked up to a diagnostic machine.

Says SAMS registering low voltage.

Also had the old alternator bench tested and it is not showing any faults and give a good voltage.

thin it may be off to a Independent Merc Mechainc to sort.

insame1

I would start checking grounds. Also check the rear sam for water damage.

Sipstrassi

Where do i find the SAMS?

Plutoe

You have three SAM's which one did the diagnostic tool say was faulty!!---no HS

Sipstrassi

Sure they said the rear one.

I take it this is in the boot somewhere?

Plutoe

Yes, and depending upon the steering wheel location the rear SAM is on the same side as the steering wheel---simply pull the cover back and view, however without the tools what are you going to do look at it!!

Sipstrassi

I have a screen shot of the data that the garage has.

Plutoe

You can only see half the page---make the image smaller, all I can see is that you have five body fault codes!!

Sipstrassi

insame1

You can find it the same place i did, google.

Plutoe

Based on your first post, it would seem that you did all you could to improve the low voltage reporting(although I think you did not have to make all the changes you did)----------after all said and done when you clear all the faults---do the faults return---if the do then my guess is that you have a faulty front drivers side SAM---why because that is where the voltage is sensed and reported when low to the IC and others---remember the SAM is a place for fuses and relays to be activated but also houses a group of microprocessors that preforms the voltage switching!! one is not functioning!!

Rudeney

The W209 has only two SAMs - on in the front, one in the rear. These are integrated into the fuse panels under the good and in the trunk.

Rudeney

I'd clear the faults and see if they return. 13.6v is a little low. It should be 14v+ even with "all" accessories on and the engine running, though that's not really low enough to trigger faults. It's possible you had a bad battery or alternator that damaged a SAM. They are a bit fragile when it comes to voltage fluctuations.