BMW M6(2006) please help to identify problem with gearbox

BMW M6(2006) please help to identify problem with gearbox

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karolis

Original Poster:

5 posts

107 months

Thursday 16th April 2015
quotequote all
attaching photo with the computer diagnostic notes.

The situation now is that i am trying to put the 1 gear from neutral ,but only thing i hear is that the gearbox hitting but cant put the gear . Does someone have any considerations?

Schermerhorn

4,342 posts

188 months

Thursday 16th April 2015
quotequote all
Sounds like clutch position sensor.

TheEnd

15,370 posts

187 months

Thursday 16th April 2015
quotequote all
There's one code for the clutch position sensor, 4FA0 - Clutch position deviation, but when the sensor goes, you normally get 2 other codes
510D - PLCD Clutch position sensor signal
510E - PLCD Clutch position sensor redundant(backup)signal

I believe that when the slave cylinder or the release bearing has a problem, you might have some similar effects.

karolis

Original Poster:

5 posts

107 months

Thursday 16th April 2015
quotequote all
Before these problems(about 2month ago) i checked the car preventive and the person who checked said that there are problem with some kind of sensor and that the clutch starts slipping.

Schermerhorn

4,342 posts

188 months

Thursday 16th April 2015
quotequote all
karolis said:
Before these problems(about 2month ago) i checked the car preventive and the person who checked said that there are problem with some kind of sensor and that the clutch starts slipping.
Does the car drive still?

Take it to 3rd gear at about 40mph and try and accelerate without going down any gears. The car should give this warning. The torque 'wall' will prevent any meaningful acceleration from happening and you'll get this bong.



If so, it's more than likely the clutch position sensor.

As a precaution, change the clutch and flywheel anyway. The SMG unit and the gearbox are fairly robust. The clutch and flywheel are......not so much.

The faulty position sensor (which comes about as a result of the 'dragging' clutch) is the all the warning you need to get it changed before it truly knackers up.

karolis

Original Poster:

5 posts

107 months

Thursday 16th April 2015
quotequote all
but the problem is that i cant select any gear, when i push the gear switcher to right side from n position i hear noises like it tries to hit the gear but it doesnt and on dashboard shows n . nothing else i can do

Schermerhorn

4,342 posts

188 months

Thursday 16th April 2015
quotequote all
karolis said:
but the problem is that i cant select any gear, when i push the gear switcher to right side from n position i hear noises like it tries to hit the gear but it doesnt and on dashboard shows n . nothing else i can do
Unusual. It could be the hydraulic SMG unit itself, release bearing or clutch cylinder.

Do you have a warranty?

karolis

Original Poster:

5 posts

107 months

Thursday 16th April 2015
quotequote all
no the car is 9 years old

Schermerhorn

4,342 posts

188 months

Thursday 16th April 2015
quotequote all
karolis said:
no the car is 9 years old
Has the clutch been replaced before?

If it has not, this may be the most logical place to start. It may all be seized up and need replacing. It's not cheap but ECP do it for around £800 clutch and flywheel these days. You'll also need the clutch fork, flywheel bolts, clip and the clutch position sensor. That itself is another £350 or so. Labour is going to be around £400.

There's no cheap fix on these cars unfortunately.

karolis

Original Poster:

5 posts

107 months

Thursday 16th April 2015
quotequote all
no never before, and now it is 96000km on odo. yes i agree you have to pay for exciting things wink

jcolley

183 posts

125 months

Friday 17th April 2015
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- First step is to check the fluid level in the hydraulic reservoir. Top off if necessary. Low level would allow the pump to reach it's pressure target setpoint avoiding an error code, then fail to reposition a shift rod after exhausting it's fluid capacity operating the clutch.

- Next is an accumulator pre-pressurization test to verify the nitrogen charge is in specification. This is easily performed in INPA, ISTA, or DIS (all BMW diagnostic tools)

- Then an SMG adaptation to verify all the calibration setpoints can be properly met. If there is a pre-existing problem, the adaptation routine *may* find it for you and error out giving a specific failure mode. Please disregard any advice you have seen elsewhere about not performing adaptation on a used clutch/flywheel. This is based purely on speculation with absolutely no solid data collection. I have performed adaptations on thirty or more of these all on used clutches, my personal car probably 100 times or more logging the results.

- Replacing the SMG pump motor relay is also beneficial. Over time the contacts in the relay become arc-pitted due to constant cycling (current interruption) of an inductive load. This pitting leads to high resistance, therefore a high voltage drop on the contacts and less voltage delivered to the motor, thus less motor torque and reduced pressurization ability. This is cheap and easy to rule out other problems.

- Finally, possibly first...are there any other codes present in *any* other module (computer) which may be indicative of a total car voltage problem, lending to SMG voltage problems?

M777CUS

267 posts

134 months

Sunday 19th April 2015
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Schermerhorn said:
Has the clutch been replaced before?

If it has not, this may be the most logical place to start. It may all be seized up and need replacing. It's not cheap but ECP do it for around £800 clutch and flywheel these days. You'll also need the clutch fork, flywheel bolts, clip and the clutch position sensor. That itself is another £350 or so. Labour is going to be around £400.

There's no cheap fix on these cars unfortunately.
given what they used to be this actually isnt too bad.