Mercedes-Benz Forum banner

1 - 14 of 14 Posts

·
Registered
MB SL500 1990, Alfa Romeo GTV 3.0l V6, Alfa Romeo 156 JTD
Joined
·
29 Posts
Discussion Starter #1
Anyone know how to test a roll bar controller? my roof and roll bar wont work, the fault codes are 3 and 4 but neither will clear, the battery is new, i do have a seatbelt issue where no power is going to the seatbelt relay but i'm guessing this comes from the rollbar controller anyway, i'm looking at the roll bar before the roof because i believe the roof wont work when the roll bar wont
 

·
Registered
Departed 1998 SL500 (and the Pano is in Bogota)
Joined
·
11,121 Posts
RollBar codes for RST :
3=Volts supply.
4=Driver seat belt lock relay open circuit, or short circuit to battery + or ground (-)

2=rollbar control module. So you are lucky you do not have code 2.


So if you don't have code 2, then based on 3 & 4, the problem should be your driver's seat.
 

·
Registered
MB SL500 1990, Alfa Romeo GTV 3.0l V6, Alfa Romeo 156 JTD
Joined
·
29 Posts
Discussion Starter #3
Hi could it be the passenger seatbelt on a rhd car? As this doesn't have power to or from the connections?
 

·
Registered
MB SL500 1990, Alfa Romeo GTV 3.0l V6, Alfa Romeo 156 JTD
Joined
·
29 Posts
Discussion Starter #4
And also i'm not getting any lights on the dash or switch to suggest a problem, the only way i even know the switch is working is because i can hear a relay sound coming from the rollbar controller
 

·
Registered
MB SL500 1990, Alfa Romeo GTV 3.0l V6, Alfa Romeo 156 JTD
Joined
·
29 Posts
Discussion Starter #6
i'll test the other seat then feed the same voltage through the connection that hasnt got a live and see what happens, hopefully this will be the problem then i'd just have to find out why it isnt getting any power
 

·
Registered
MB SL500 1990, Alfa Romeo GTV 3.0l V6, Alfa Romeo 156 JTD
Joined
·
29 Posts
Discussion Starter #7
Does anyone know how much voltage the controllers/ modules need ? mine is showing 11.75 which has been suggested is to low
 

·
Registered
Departed 1998 SL500 (and the Pano is in Bogota)
Joined
·
11,121 Posts
11.75 seems low. Our cars are very sensitive to voltage, but I thought you said your battery is new.

What happens if you do it with engine running ?
 

·
Registered
MB SL500 1990, Alfa Romeo GTV 3.0l V6, Alfa Romeo 156 JTD
Joined
·
29 Posts
Discussion Starter #9
the voltage does go up when running but didn't want to clear the codes withe the motor running in case it does damage, the battery is new but been messing with lots of bits n bobs so guess its run low, still starts the car but could do with a charge, does anyone know if the dignostics can be messed with when the cars running?
 

·
Registered
Departed 1998 SL500 (and the Pano is in Bogota)
Joined
·
11,121 Posts
What are you using to scan and clear codes ?
I use Carsoft and some of the diagnostics were done with engine running, and I cleared some minor codes when it was running. But I did not have your codes so can't really comment on that.
 

·
Registered
Departed 1998 SL500 (and the Pano is in Bogota)
Joined
·
11,121 Posts
So you have the old system and using the simple method of counting blinks.
Sorry I am not able to help much as my car has the newer system and can use automatic scanner to do the work (besides, I can't count. Take off my shoes to count to 20, pants off to 21).
 

·
Registered
MB SL500 1990, Alfa Romeo GTV 3.0l V6, Alfa Romeo 156 JTD
Joined
·
29 Posts
Discussion Starter #13
yeah thankfully i can use the good old paperclip method, altho like i said im not sure such technical methods can be practised with the motor running
 

·
Registered
MB SL500 1990, Alfa Romeo GTV 3.0l V6, Alfa Romeo 156 JTD
Joined
·
29 Posts
Discussion Starter #14
Does anyone know what voltage is being sent to the seatbelt solenoid and what it returns? I'm assuming it from and to the roll bar controller
 
1 - 14 of 14 Posts
Top