SL350, command system

[Bil2108]

I have a 2006 SL350 that the SRS light comes on the windscreen wipers then do not work and the roll bar light comes on then there is a clicking in the seat belt over my shoulder the radio then turns itself on and off does anyone know the cure I have had it checked at Mercedes and no one has the answers

Bill

 

[npuk]

Have you had it put on STAR to check for any fault codes logged?

 

[Bil2108]

Yes they could not find any faults

 

[Pitts Pilot]

Is this an intermittent fault, or a constant 24/7 problem?

 

[redbaron]

Failing convenience battery would be my starting point....

 

[Bil2108]

It is intermittent might happen once a week

Regards

Bill

 

[Bil2108]

I have had the Battery checked all ok

Regards

Bill

 

[Burger]

This sounds exactly like the symptoms when the convenience battery is nearly flat. I appreciate you say you've had it checked, but batteries behave differently under load etc. I've had the exact same things happen on my SL350 when I had it in pieces to fit extra audio equipment etc. I ran the convenience battery flat and then all hell broke lose including SRS and roll bar lights etc. I suspect the clicking in the seat belt over your shoulder is either a relay in the box behind your seat or part of the roll bar activation etc.

If the battery itself is perfectly OK there could still be something wrong in the electronics controlling it or something really simple like the battery terminals are not clamped up correctly.

Regards,

 

[s88]

R230 - 2006 sl 350

I have a 2006 SL350 that the SRS light comes on the windscreen wipers then do not work and the roll bar light comes on then there is a clicking in the seat belt over my shoulder the radio then turns itself on and off does anyone know the cure I have had it checked at Mercedes and no one has the answers

Bill

Had a run out today ( A good Wack of Flanai's Yorkshire run, 250 miles) and had the same faults again. Took almost 2 hours for the SRS to go out and the command functions/windscreen wiper/heated seats to become useable again.
This normally only lasts a few mins, so not sure why so long today.

Car has been recently used and I have had the convenience battery on charge.

Just checked the convenience battery terminals and they are tight.

No codes ever showed up on STAR on my last service.

No passenger carried today, if that makes a difference.
Passenger also felt that the seatbelt was tightening up when we had this fault yesterday!

Does anyone have any more ideas.

Many thanks,

S

 

[redbaron]

The fact that it all starts to work still indicates to me that the battery is failing to hold charge properly and is activating the functions as it charges up from the alternator on a long run. I would take it to an indi and have it checked over - or borrow a known good battery and change it ( obviously the secondary battery not the primary)

 

[ming]

This may sound extremely stupid but how does the command sat nav work? The manual is toooooo long simple guide please?

 

[s88]

A search on the web and the "other MB site has had a similar question and seems to suggest the SAM unit - drivers side.

Could anyone advise where the SAM units are hidden?

Many thanks,

The info below is copied and I think written by a guy under the name Televsion; thanks to him.

"Well I am going to say drivers side SAM

The wipers are on it.
The SRS system is on it.
Comand is on it.
The seat lock sensor is on it.
Front drivers seat is on it.
The lamps are on it.
The cluster is on it.

Now if a SAM loses information the Can will keep sending out signals till it finds something, usually after 15 mins of driving when the important activity has died down. This is the only component to behave like this.

The odd man out is the roll bar that is connected to the rear SAM, but also info needed as a safety item, but all part of the CAN B, as are all of the other faults.

At this stage it is worth removing the passenger SAM and looking in side to check for the slightest corrosion on the PCB as moisture gets into this via the vent in the wing, and this SAM can blow the drivers side with ease, I know been there and had it".



S88

 

[s88]

Sat nav

This may sound extremely stupid but how does the command sat nav work? The manual is toooooo long simple guide please?

press NAV, enter the destination, long hand or post code, hit ok and ok again start guidance.

 

[Bil2108]

Hi,
Have you tried changing the SAM unit?

I might have to look at this as it is starting to drive me mad

It has been good for a week then started again

Bill

 

[s88]

SAm unit

Hi,
Have you tried changing the SAM unit?

I might have to look at this as it is starting to drive me mad

It has been good for a week then started again

Bill

Bill, no I have not looked into the SAM unit, not sure where it is?

Have had the batttery on charge, and things seemed ok after that; car does not get enough use which may be an issue.

Would appreciate it if you could keep me informed how you get on.
Back to work next week so a few months away from the car for me!

Cheers,

S88

 

[Pitts Pilot]

Failing convenience battery would be my starting point....

I would be careful before you completely dismiss the rear battery as a possible cause.

Lead acid batteries have a 'prime of life’ of about 2-3 years, after that it’s all downhill in terms of taking/holding/and delivering charge. How old is the battery?

Your battery may charge fine. It will almost certainly test fine for voltage, but as someone else has pointed out it's when it is under load that the chips are down.

We have all seen a car with an indicator on and the rear lights flashing too, out of sync with the indicators – an old battery that is failing under load, and messing with the vehicle's electrical system.

It’s difficult to think of too many ways to put the rear battery under load to test it, but raising or lowering the roof without the engine running certainly takes some charge, as does using the command audio and adjusting the electric seats, all at the same time. That would ask it to deliver plenty of current. Just have a charger on stand-by

It would cost nothing to check it could withstand this ‘torture’ test

 

[s88]

Robert,

Thanks for the reply.

I tried the "torture test", car not running and opened the roof, command on, moved the seat and had the heated seat on. No problems at all.

Did the same in reverse to close the roof. No problems.

Then started the car and had my amber rollover bar light on and the red SRS light.

Started it agin a few mins later and had restraint system visit workshop.

Started again even later no malfunctions.

Cheers,
S88

 

[Bil2108]

S88

I will try thr battery first and see how it goes will keep you posted

Regards

Bill

 

[Bil2108]

I will let you know how it goes, may change the battery first as the cheapest option

Regards

Bill

 

[Bil2108]

Hi,

I tried the Battery and it is still the same anyone have any further ideas?

How about relays!!!

Has anyone changed the SAM unit?

Regards

Bill