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mike_a_mechanic, Mercedes Mechanic
Category: Mercedes
Satisfied Customers: 5471
Experience:  17 years experience as a auto mechanic, foreign and domestic.5 years running my own repair business.
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Hi, The car is a Nov 2003 SL55 AMG with 61K mls. When the

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Hi, The car is a Nov 2003 SL55 AMG with 61K mls.
When the gearbox is in manual `M' mode, the mode occasionally moves back into `S' mode without being selected. The gear-change operation of the box is otherwise flawless in all modes and has had a main dealer gearbox oil and filter change some while before this problem emerged. The fault doesn't seem to be temperature related (engine or ambient) and I was wondering if it may be caused by a dirty or faulty fuse in the mode selector circuit. The button on the centre console doesn't appear to be the cause.
Thank You.
Russ Leaviss
07990 830660
Hello, welcome. My name is***** will do my very best to assist you with your question. I apologize if you have been waiting long for a response.
Are there any warning lights coming on?
Customer: replied 3 years ago.
Hi Mike, No warning lights on.
Hi, the issue that you are having is caused by a failing gear/mode selector switch which is located in the gear shift assembly. This switch will need to be replaced to cure this issue. This was a common problem.
Customer: replied 3 years ago.

Thanks Mike, How difficult / accessible / expensive is the job to change the gear/mode selector switch?

Customer: replied 3 years ago.

Relist: Incomplete answer. How accessible /easy to change / expensive is the gear mode selector switch please (I did originally pay extra for an in-depth reply) Thanks Mike.

To replace this switch the gear shift assembly has to be replaced as the switch is sold as a assembly. This repair will require about 2 hours of labor and the part will cost about 300
Customer: replied 3 years ago.

Is area in question underneath the actual gear lever/selector, if so, is access achieved from inside the car or from underneath please?

Access is achieved from inside of the vehicle and the linkage is removed underneath the vehicle.
Customer: replied 3 years ago.

OK thanks. Is this switch directly underneath the square button on the top LHS of the console that switches the Mode, or is it actually on the gearbox itself please?

It is under the console square button. Thank you.
Customer: replied 3 years ago.

£300.00 for a switch sounds mad. How much else is included for that, and would the aftermarket be a better bet. Also could a non-Merc Franchised dealer do the job?

A aftermarket switch would be fine, and a independent shop could handle the job with no problem. The shifter assembly is included in that price.
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