brake switch replaced, shift now stuck ??

[television]

I will come back on this a bit later

 

[culpeper]

am going to try battery disconnect tomorrow, to see if reset changes anything.

 

[television]

I was going to say maybe a power down just in case something locked up, though this part of the car should be dead with the key out.

The brake lamp switch does carry CAN speed signals that the BAS uses, the gear shift does need to know the status of the car speed, hence the interlock.

Although Alex has said the brake lamp switch should not be a reason for the blown shift module one never knows, it is also unusual to have a brake lamp switch that failed in the same way as yours, it does not take much to do some further damage.

I can print off the instruction for you to change the gear ECU, there are loads around now being broken up, it has to be a late car like yours for the earlier versions do not have much in the way of a CAN

You could ask member Rob Parker if he has one

 

[culpeper]

Thanks a print off, off the instructions to change the gear ECU would be great. Have been looking for detail already. Will update as goes along in case someone else has same problem.

The brake light being on all the time was strange, as I would have thought off would be the norm, but who can tell.

Thanks for the help

 

[television]

I am 90% sure that Mercedes run the live 12v to the switch rather than use the ground side of the lamp

 

[television]

Your car, can I have the next 3 numbers after WDB202 086 or 088

 

[Alex Crow]

Have you checked the fuses in the K40 relay module? Specifically fuse f2 10A
They are under a black plasticx cover (4x philips screws) in the engine bay, passenger side.

Beyond that, you have the stop lamp supression relay, k55, which is a yellow relay mounted in the passenger footwell.

Please do not buy any parts until you have proper diagnosis! Our suggestions here are not intended to be a shopping list, more like pointers for those in the know.

 

[culpeper]

Thanks all will be checking all asap. Not been able disconect battery as yet so hope weekend. Have checked fuses, pasanger side, the other day, but will do so again and test for contunity on all this time rather than visual.

I have a diog unit (not pucka one) but it gave no faults bar P0170 fuel trim and P0130 co2 sensor circuit ( bank 1 sensor1) pending.

thanks for all your help

 

[culpeper]

Your car, can I have the next 3 numbers after WDB202 086 or 088

Car number is WDB 018

Thanks for your help

 

[culpeper]

The update 15 -1- 2013

Battery charged and reconnected, starts up like a tank, almost as though there is no auto choke as tries to die when using accelerator some miss firing. BAS & ESP light came on also.
As was dark will look again in next couple of days when I have time.

Thanks all.

 

[culpeper]

The update 15 -1- 2013

Battery charged and reconnected, starts up like a tank, almost as though there is no auto choke as tries to die when using accelerator some miss firing. BAS & ESP light came on also.
As was dark will look again in next couple of days when I have time.

Thanks all.

ITs ALIVE

Dont know how, as was just fiddeling around looking for possible causes, gear box was still usless with out override and would not move in gear. Was still running like pig misfiring ect.

so checked maf, car died

dioged several times and deleted logs

checked general plugs for looseness

Decided to check box oil wile fiddeling around so ran car to 80 deg and wile I was doing this tried the box with override several times, when it stuck in N. then did then did not, no forward or reverse when in gear. Same as before

All of a sudden; gearbox worked, dash showed gear selected, car pulling forward and reverse, engine running ok ish.

Been on road and all seems ok although there seems to be a slight loss of power when driving now and then so will diog later on to check for any log entries

Dont have a clue how but who cares its working

Thanks all for input :wink:

 

[culpeper]

Well ile be blowed fault came back with auto box, however, the following happens.

No auto box no indicatrion of gear position on dash

Start engine and with override put in gears but no power / pull

engine warmer and all of a sudden can get into gear but sticks in N

get to full work temprature, can get into gear but stick in neutral.

turn engine off lock and unlock and go to pre start with key and low and behold P comes on dash all gears ok ( can happen straight away or takes couple of goes).

Drive car and all shifts smooth runs ok

any suggestions

Have looked at box level ( not mb stick) and looks ok but may be wrong.. Is above a possible fault or is there a possible sensor fault ( had co2 bank 1 pending come up and at one time said fail ) :lol:

 

[mersum1es]

Have you already checked TCU (transmission control unit) that there is no oil inside (Television gave instruction to you)?

 

[culpeper]

have not checked, thanks will look for detail of what to do

as it seems to sort out when to operating temp can see affect but who knows

Thanks

 

[Alex Crow]

Again, this suggests a failing selector module, which is not uncommon.