Popo Pantoja

I own a 2003 sl55 amg. In d past, d roof wont open immediately after i start d engine. It would open only after say a 20 minute drive. I recently drove d car again after a 3 month hiatus. The roof still wont open after i start d engine. And after a 45 minute drive, only d luggage cover would rise/ open. But d roof wont slide/follow. So i pressed "close" and d luggage cover closed. The next day, i started d car again, and tried to open d roof, but this time, the compartment cover wont evenrise. Could it be that i need to replace d front battery? Engine starts without any problem.

carlsturm

The 'front' battery is your starter battery. Your trunk battery is the Accessory battery. If it were a battery issue I'd think it would be the trunk battery however I'm not sure it's a battery issue. When there's an issue with the accessory (trunk) battery you'll usually receive a dash message indicating your "convenience functions" are inoperable . I'm sure others with more knowledge than I will chime in. Good-luck.

skylolow

From your description I'd say the trunk battery is the first thing to look at. The system does exactly what your saying it does if it doesn't have enough power the system turns off certain items. For example if its really low your door lock may not open or lock electronically. Starts with cutting off the high draw items first like the roof. Though as Carl said you should get dash error "convenience functions". But who know maybe another glitch not triggering an error on the dash.

First thing to do and probably the cheapest thing to do is check the volts of rear battery. If its only reading like 6 volts chances are high the battery just needs to be replaced. If its like 11 volts you can put a trickle charger on the trunk battery and leave it on for a few days. A good trickle charger can actually bring a battery back to life. Then unhook it and check the volts of the battery and then start the car and see if your roof works, great if it works you found the problem. Then monitor the battery after that. If it sits a day or two and the roof isn't working again then just replace the battery.

If the battery is original or more than 6 years old just replace it to start with and even if it doesn't solve your problem at least you took care of maintenance issue.

Joe Chu

Since you drive your SL not very much............. I think the main battery should be drained and the "Consumer shut off" function was activated at that time.
In this case, most function/system will be limited, for instance: AC blower 50%, seat heater, roof top, radio etc........It depends on the battery condition and what stage of consumer shot off was activated.
Actually, the message will be popup in IC.

FxFormat

With the engine running, the battery should be getting full juice to operate the roof. My bet is on the pump not having enough fluid, that's the problem with mine, this morning i checked the pump and the fluid level was way below the bottom mark. I put it to the top mark, and cycled the roof a few times, then opened the air bleeder screw to bleed some air out and now it's working again. I had the same symptoms you did, check the pump and see the hydraulic level.


This was my reservoir this morning, your level should be near the top of the top triangle.




Pump is under the trunk in the spare tire area, lift up the foam noise insulator on the left side and you'll see it.