Auto won’t go into drive - SOLVED (I think)

[AntStark]

No symptoms..just pulled up to get some fuel this evening..tried to leave but my 5 speed auto won’t go into drive. It’ll quite happily go in reverse, neutral and park but not drive. Somethings not releasing
Brake lights work (as does hood) so don’t suspect brake switch. Anyone had this? Duff speed sensor maybe? Luckily it broke down literally outside my mot garage.

 

[NZ00Z3]

There is a Bowden cable from the ignition switch to the auto lever mechanism. When it sticks, it usually does not let you out of park. Maybe it has not released enough to allow you into Drive.

Pop up the black Auto stick surround. The Bowden cable comes in to the top/heater controls end. By memory from the left. Work the ignition switch and watch to see that it is moving fully.

 

[Rudyrov]

I drive a manual 5 speed 2.8 so not too familiar with automatic model. My question, does the automatic have a manual release like many / all newer cars do? This is usually a key slot near the shifter assembly. Thanks

 

[Duncodin]

I drive a manual 5 speed 2.8 so not too familiar with automatic model. My question, does the automatic have a manual release like many / all newer cars do? This is usually a key slot near the shifter assembly. Thanks

Mercedes had a little hole with a flap next to the D. You could stick a pencil down past the flap to release the lock to get it in to D.

Having said that it would need to be pretty serious for the Merc to decide to completely block 'D'. Something like really low tranamission fluid might do it. For something minor like a speed sensor it would allow the car to go into gear but restrict speed - limp mode.

But my 'automatic' experience is only with mercs. Sorry. No idea whether BMW has a release switch or what kind of fault would lock you out of 'D'.

 

[Rudyrov]

Found this on the tube...

View: https://youtu.be/o0LrZopOKC0

 

[AntStark]

Found this on the tube...

View: https://youtu.be/o0LrZopOKC0

Thanks..it releases from park no problem..and will drive in reverse too

I was thinking if it was a sensor it would probably throw a fault code or engine light

 

[AntStark]

Went back to the garage this morning being prepared for it to be towed home. Fired it up. and it went into drive with no issue ! Anyway, I got it home so will get it on the scanner and check for fluid leaks etc. All very strange

 

[AntStark]

Car scanned.. No fault codes anywhere. Wonder if it was just a sticking bowden cable. Will take the gear stick surround off and have a look at some point

 

[Rudyrov]

I would lubricate the mechanism and cable that control the shifter lock. It's a mechanical system designed to prevent the shifter from moving out of park if the ignition key is not in the "on" position, a safety interlock brought to you by "Big Brother".

 

[AntStark]

I would lubricate the mechanism and cable that control the shifter lock. It's a mechanical system designed to prevent the shifter from moving out of park if the ignition key is not in the "on" position, a safety interlock brought to you by "Big Brother".

Thanks I will.. it did feel like a mechanical issue rather than something wrong with the gearbox. If the gearbox was at fault it I am sure it would have thrown a code and shifting would be erratic.

 

[AntStark]

I took the gear selector housing off this morning to have a peek inside and also just give it a general clean with some cotton buds and WD40. Whilst doing so I noticed this fingernail piece of plastic had broken.. it was covered in dirt so not a new occurance

it seems to have come from here which meant this linkage had quite a bit of play in it

the end of that linkage fits in a little plastic slot when you are in drive

What I think happened was because of the play the metal linkage caught on the edge of that slot rather than going into it.

Sort of relieved that it’s not something gearbox related .. wondering if I live with it knowing how to fix it on the off chance it happens again or add it to the long list of ‘stuff I need to persuade @Lee to help me replace’ .
Anyway sods law .. i’ve got a ABS light on the Merc to deal with now