R129 SL Roll Bar Problem!

[SG1]

Evening everyone.

Wondered if anyone has any experience with the following issue - the car is really starting to annoy me now!

The car is a 1997 R129 SL. I think the battery went slightly flat as I hadn't started the car for a few weeks. (Still started but took a tad longer than usual). The drivers side window didn't want to lower when you open the door but that is now working fine. The roll bar switch is permanently illuminated and doesn't raise the bar, the soft top is also not working as I believe this is all related although the light is not illuminated.

Any ideas anyone before I park the car somewhere and forget about it!!

 

[BTB 500]

Have a read of this ... very similar (also caused by low voltage):

http://www.mbclub.co.uk/forums/elec...rollbar-switches-permanently-illuminated.html

Solution in the end was having the fault codes read/cleared.

 

[Vlad]

You need to get the battery charged up and then go from there....I suspect a lot of the issues are down to the weak battery.

 

[ivan1983]

Disconnect battery, recharge and ensure it holds it. Reconnect.
Start engine hold window switch down, keep holding down for 10s after down. Put windows back up and holding switch up for 10s. Roof should work now, if not try turning car on and off and trying roof switch again.

It sounds like you have reset the driver side window but not the passenger?

 

[BTB 500]

Disconnect battery, recharge and ensure it holds it. Reconnect.
Start engine hold window switch down, keep holding down for 10s after down. Put windows back up and holding switch up for 10s. Roof should work now, if not try turning car on and off and trying roof switch again.

Worth a try but none of that worked on mine ... it needed the fault codes clearing via STAR.

 

[SG1]

Have a read of this ... very similar (also caused by low voltage):

http://www.mbclub.co.uk/forums/elec...rollbar-switches-permanently-illuminated.html

Solution in the end was having the fault codes read/cleared.

Thank you, read it. Very useful

 

[SG1]

Disconnect battery, recharge and ensure it holds it. Reconnect.
Start engine hold window switch down, keep holding down for 10s after down. Put windows back up and holding switch up for 10s. Roof should work now, if not try turning car on and off and trying roof switch again.

It sounds like you have reset the driver side window but not the passenger?

Thanks, I will try this procedure tomorrow if the weather is ok hopefully and update.

The left window was fine, it was just the right which I found odd.

 

[SG1]

To update, I've tried to reset with no luck.

The roll bar is still illuminated permanently with no change.

Any ideas of where to go from here, sensors/fuses?

 

[Mercedes cozy]

My friend had the same issue, his car had to be reset on a STAR diagnostic machine. All ok after a simple reset.

 

[BTB 500]

As mentioned, get the fault codes read & cleared on STAR. And don't let the battery get low if the car isn't a daily driver - I've kept mine on a maintenance charger ever since!

 

[ivan1983]

I use a battery isolation switch to disconnect the battery quickly.
Although this does mean I need to re synch the windows each time i use the car!
At least I "invested" in a star should I ever need to do a clear down of codes

 

[SG1]

Thanks, I will get that done next.

The car isn't a daily driver so I'll keep the battery disconnected I think.

 

[SG1]

Just to update;

My mobile Mercedes specialist mechanic serviced another car recently, I asked him to put the R129 on STAR and check what he found whilst he was here. He cleared the faults and the roll bar now seems to be functioning as it should.

I'm just debating whether to disconnect the battery now or put a trickle charger on it as it isn't used much now.

 

[Lotiman]

Go for a CTEK battery conditioner or similar. I've got 2 of my rarely used cars on one each all year round and never have any problems with starting when I do use them. A lot less messing around than disconnecting the battery.

 

[Hawkwind]

Maybe something like this would work if you don't have convenient access to a mains electrical outlet?

4.5W 12V Smart Power Solar Panel Battery Charger for Trickle Car Boat Motorcycle | eBay

Never tried one myself, but they might be OK

 

[SG1]

I've disconnected the battery now as the car is outside and covered. I won't be using it over the winter anyway.

Thanks for the suggestions

 

[rajinder_1]

I've disconnected the battery now as the car is outside and covered. I won't be using it over the winter anyway.

Thanks for the suggestions

Maybe try locking it manually and not arming the alarm as that drains a lot of battery too.