SL350 2011 WIPER ISSUE

[MBGB]

Got an issue with the windscreen wiper not working and the orange warning roll bar symbol comes up when the stalk is pushed or turned.
Checked the voltage in the boot battery well over 12 volts, but strangely when I move the roll bar switch on the central console up or down the windscreen wipers work again.
Anybody had a similar issue like that?
Checking the battery in the boot which is a proper MB battery dated 2016, is there a chance they fitted the wrong variant causing this issue?

 

[LostKiwi]

Highly unlikely as you're dealing with two totally disparate systems.
In general this type of fault is a bad earth somewhere.

 

[John Laidlaw]

Interesting thread here which covers a number of 230’s with similar symptoms...
https://forums.mercedesclub.org.uk/...d-roll-bar-airbag-light-clicking.84746/page-3

 

[MBGB]

Just had a chat with a Merc dealer and they had a similar issue recently, and stated it was caused by the wrong 12 VDC Battery being fitted in the boot, albeit like mine it was installed by them!!! The car is ALWAYS in the dry so water getting in isn't an issue like the threads indicated by John.
It is strange that if I lift the roof control lid in the central console and operate the roll bar in either direction it clears the fault on the wipers and water. So in my mind it must be a voltage issue! Any thoughts?

 

[John Laidlaw]

Just had a chat with a Merc dealer and they had a similar issue recently, and stated it was caused by the wrong 12 VDC Battery being fitted in the boot, albeit like mine it was installed by them!!! The car is ALWAYS in the dry so water getting in isn't an issue like the threads indicated by John.
It is strange that if I lift the roof control lid in the central console and operate the roll bar in either direction it clears the fault on the wipers and water. So in my mind it must be a voltage issue! Any thoughts?

Sorry it was a long thread and if you go back past the leaking issues there was also potentials in EIS and SAM- I should have mentioned apologies

 

[MBGB]

John,
Thanks for that, yes I did read what was said on page 3 of that thread, but mine appears dry as a bone and no blockages at all.
Strange that these faults sound so common in so many SL's.
Press or turn the windscreen stalk, roll bar light comes on and ticking behind the driver and the intermittent flashing of the airbag light.
I found just keep trying and eventually clears.
STAR flags up nothing, other than my engine management light came on last week saying thermostat on the STAR system which I got them to replace. Starting to wonder whether that was necessary now!! Said on the print out "Jams in the open position, coolant temperature rises too slowly"
Seems to me too like Kiwi thats its a earth issue somewhere.
Any further thoughts rather than going for an EIS replacement on the off chance?

 

[John Laidlaw]

SL’s are quite complex, mechanically and especially electronically!
So many issues do boil down to aux battery issues, but not it seems in your case.
My 2008 example had a fair pile of glitches which centred around the steering column and a front passenger SAM which refused to communicate.

 

[MBGB]

John,
Thanks for that. Just been exploring under the bonnet. Looks brand new and no water anywhere. Went round the block, wiper failed to work initially, then went to it and it worked fine. At the time of pushing or twisting the stalk I can confirm the roll bar light came up and also the airbag light flashed and the ticking behind me in the fusebox, so really startung to think its a bad earth somewhere.

 

[MBGB]

There I thought I had got rid of it, but its back.
Roll bar light on central dash on throughout/airbag light flickering central dash and a ticking definately in the front fuse box now O/S............all come on and therefore can't use the wipers. After keep trying eventually comes back grrrrrrrrrr
Anybody else had this, or should I take all the fuses out and clean them up, can't be that simple!!! can it?

 

[MBGB]

There I thought I had got rid of it, but its back.
Roll bar light on central dash on throughout/airbag light flickering central dash and a ticking definately under the O/S steering wheel............all come on and therefore can't use the wipers. After keep trying eventually comes back grrrrrrrrrr
Anybody else had this, or should I take all the fuses out and clean them up, can't be that simple!!! can it?

 

[MBGB]

STAR system says windscreen wipers not parked thats the only fault very odd!! Rear Battery brand new and showing 13.4 V

 

[peterws1957]

STAR system says windscreen wipers not parked thats the only fault very odd!! Rear Battery brand new and showing 13.4 V

Shot in the dark, but could not this be a faulty wiper switch causing some sort of short?

 

[alexanderfoti]

Have you also checked for water in the sills, where the canbus connectors are....

 

[MBGB]

Yes both checked stalk is fine also sills bone dry.............really frustrating. Ironic that the dealership have an identical problem in another SL and they can't find the fault. I'll keep you informed.

 

[LostKiwi]

At the risk of being obvious have you checked the wiper motor earth?

 

[MBGB]

Thanks for that, where do I find the simplest location to check that, other than on the actual motor?

 

[LostKiwi]

Check the wiring from the motor. Not sure on your particular car but there is usually s brown wire that will attach to the body via an eye connection and a bolt. You may need to follow the wiring harness to find it. Undo the bolt, clean everything with emery paper, lightly grease and reassemble.

 

[noonboots]

My SL was suffering from all kinds of random warnings and warning lights coming up. It was fitted with a new 096 standard battery which always went flat after about 10 days although it always read correct voltage when charged. For no other reason than it wasnt an AGM I changed it. In the three months since I've not had a single issue of flat battery or any warning lights. I'm not saying it's cured anything for sure but it's a massive coincidence. The 096 I took off is now on a friend's VW van.

 

[MBGB]

Thanks both for that. It is interesting that the Chief Trainer at Mercedes Milton Keynes told me that if it was garaged, don't lock the car as I normally do, especially as I don't use it as often as I should, for obvious reasons!

Regardless of a new Merc battery in the rear dated 2018, he told me to get a trickle charger set up direct through the rear battery. He said 100% it would cure all my issues. The main reason:
These cars are for daily use, not for leaving to one side. I suppose there is something in that too, but didn't want to buy yet another trickle charger, but I suppose as I get more and more peed off with this crap I will do as he says. Would be interesting to see if he's right, as the problem does seem to recify itself on long runs!!!

 

[Blobcat]

I’ve a friend with an SL500 R230 that sits for months at a time, he has a charger on the boot battery all the time and no issues at all.