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ML 420 stuck in park, not selecting gears

Chris72

New Member
Joined
Jan 5, 2020
Messages
9
Location
Wiltshire
Car
ML420CDI
Hi there, looking for advise regarding ml420 cdi, got into car this morning only to find that following starting it is stuck in park and I can not select drive or reverse, any body got any ideas ? Would also like to add that the car now starts without the foot brake being depressed.
 
Chris

Welcome to the Forum

Sometimes this can be caused by a faulty brale light switch or the selector electronics may have a fault.

There is an emergency release on the transmission. it should be detailed in your handbook

Or see here:
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Chris

Welcome to the Forum

Sometimes this can be caused by a faulty brale light switch or the selector electronics may have a fault.

There is an emergency release on the transmission. it should be detailed in your handbook

Or see here:
To view this content we will need your consent to set third party cookies.
For more detailed information, see our cookies page.

Thank you DSM, it appears that there is no emergency release on the m class and the selector is moving it is just not selecting, it also appears that there is not a stand alone foot brake switch in the cabin, it appears to be part of the master / servo brake unit.
 
Yes it is a column change and also aux battery, tested that when I had the sear up checking main battery .

A diagnostic reader, Star for preference or iCarsoft would be helpful to be able to read any fault codes. Do you have a good MB Independent near by?
 
A diagnostic reader, Star for preference or iCarsoft would be helpful to be able to read any fault codes. Do you have a good MB Independent near by?
Have ordered an icarsoft980 to hopefully get things rolling, have previously used main dealer as work used to pick up the bills but changed job over a year ago and this is the first issue I’ve had since leaving.
Anybody on here recommend a independent near to Chippenham ,Wilts ?
 
Has the Foot brake pedal Actuator failed?? thus he can start it without having his foot on the brake?
 
Will likely be the Intellegent Servo Module if the battery (including aux battery) are in good shape.

When I had a flat battery and jump started it I got this message and had to wait 20 mins or so before I could select drive.

Has to be coded to the car aswell for security reason.
 
In this situation, if it's not just a consumer battery low on charge, how does one get the transmission out of Park so the vehicle can be towed?
 
I believe the only option is to drag it onto a recovery truck with winch, but how you get it off the other end ??, I suppose you could put it on skates ‍♂️
 
Well if you have home start with a recovery service call them and tell them you need a truck and call a independant garage you say you are in Wiltshire I seem to remember a member said there was a indy in Swindon that was good,not sure of the name
 
My 2006 GL420 recently had this error but cycling the ignition a couple of times cleared the fault and got the car going. Diagnosed as ISM fault so waiting for parts to get replaced (iCarsoft EU Pro could read the fault code under the EIS module). If the ISM is totally goosed then it is stuck in Park. Skates will be needed to get it onto recovery truck as dragging it without can damage the transmission. I have put mine into Pentangle in Southampton but that is probably too far for you. The fault code really needs to be read first, preferably with a Star diagnostic as the ISM is expensive and it could be another module or something else that is causing this fault.
 
Anybody on here recommend a independent near to Chippenham ,Wilts ?
You could try PC autocare who are in Lydiard Millicent - never used them but I know they are there or if you pm me on here there might be another solution.
 
Morning all, many thanks for you comments and suggestions, so purchased icarsoft and plugged her in this threw up the below :-

226141D7-97E5-43EE-BC58-1CBE4D578E2E.jpeg 0C67D1D0-AF3D-4035-A57E-588101EF91D6.jpeg 1EBDFF78-E4C8-483E-9C30-F2BF1A08E3AB.jpeg 61ECE6EA-11EE-444D-A1BD-022D34E79A77.jpeg

Tried removing module last night but what a swine it is, have managed to drop it off the gearbox but can’t remove it, any one know what other components need removing to be able to remove it?
Can’t find any online except eBay used items any one know any other options apart from main dealer?
 
ISM is a theft related part so is usually only available from main dealer to authorised vendors. New units need to be coded to the car by Star. There is a grey market for these as you have seen as I believe used units can be cleared and recoded using Star. I would be careful though as when they fail you are stuck in park. A new MB unit fitted and coded by an Indy should be about £700 if you can get the vehicle to them. Watch the bolts holding the ISM to the gearbox as they are single use only and can snap if retightened.
 

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