SL 350 2007 "lost" the the gears

[Million]

My SL 350 from 2007 has only driven 40.000 miles - yesterday it behaved quite strange. I had stopped for a red light signal, when I began to drive, the car felt like starting in 6th gear - VERY slow - it took the idle, but no matter what I tried with the gear lever (manually 1-6, put it in N and back to D) it could barely drive. Suddenly it felt like in N, it took the revs but no gear. I pulled over, put it in P turned off the engine, started it again and everything worked?

The car has been standing still for a longer period and after the period only driven around 300 miles (with no problems) - what could cause this situation (no errorcodes or warnings)

 

[whitenemesis]

Low atf or possibly an intermittent failing speed sensor on the transmission electroplate. Had similar on my S203, Mobilo tech said it could continue like that for months or fail tomorrow.

 

[Million]

Low atf or possibly an intermittent failing speed sensor on the transmission electroplate. Had similar on my S203, Mobilo tech said it could continue like that for months or fail tomorrow.

Thx - low atf? The speed sensor - is it a big thing or should I just get done to be sure

 

[John757]

The gearbox oil (ATF) automatic transmission fluid, may need changing, as 'whitenemesis' advised.. the transmission electroplate can be tested and a new filter fitted.. by a MB independent, there are narrow oil pathways that can become blocked when ATF becomes contaminated or needs changing... these pathways affect gear selection and drive.

Get it into an indie for testing

 

[AndrewOl]

The automatic transmission fluid (atf) does not generally have a dipstick in the 7 speed gearbox I think you have. When the gearbox detects a fault it goes into a limp mode which sounds like what you experienced. Cycling the ignition often resets this. Oddly no error light is associated with this common behaviour. The errors are stored in the ecu so the best thing is to get along to an independent garage with STAR (MB diagnostic machine) who should be able to tell you what is going on. If it is just low fluid it is going somewhere. These guys may be able to help you locate someone local. Mercedes-Benz Klub Danmark. It is not uncommon on the earlier 7 speed gearboxes for the electronic controller which is inside the gearbox to develop a fault. It can be changed and there are usually exchange programs in place with the local MB dealer network.
Hope this helps and welcome!

 

[Petrol Pete]

Hello and welcome ? Do you have any proof of a gearbox service ever being carried out . ? If not it is long overdue , by time rather than mileage.