A2 1.2tdi gear selector not pushing down to 3rd, 4th and 5th gears.

[mrbizzy]

I hope you will not disqualify my post because of language, but yes, as you can see it is English. Where else to look for help with Audi if not with Germans...

 

So i am on it again - to get my A2 3L on the road, the last try.
Had to repair gearbox and ended up replacing with a good one. now all put together and i am stuck at basic settings. ECU does not throw any errors, measurements from pots are +/- in range, fluid in system is ok level and the accumulator holds pressure, also the battery has a charger connected and is a fresh one.

The problem is that during basic setting the gear selector (gangsteller) does not push downwards and as i understand that is where the gears nr 3,4 and 5 are. so RTFM 12 is a normal outcome.

I can switch all gears by hand , no extra resistance or anything on the gearbox side that would prevent that.

I tried to switch places the upper solenoid plugs N286 and N287 still not pushing downwards. Then unplugging one of the lower ones N285 then no gear selection happens at all. The diagnostic reports equal Ampers for both N284 and N285 solenoids.

So i suspect that either could be a cable to solenoid or solenoid itself that is the issue.
Next i would suspect the gangsteller itself, but i had refurbished it the previous time i tried to get that car on road and had not a chance to drive more than 100km before the fork inside the gearbox snapped and left me with a useless audi. i would think the gangsteller is ok, but who knows.
And then if those two are not the reasons i would suspect the ECU itself.

now, can you knowledgeable and kind people PLEASE help me to get on track and find the issue while i have the inspiration for it.

And if you know, is one of those 4 solenoids responsible for down-push movement? if you know, please share.

Peace and strength to you all.

MrBizzy

Moderator:

Moved to english sub-forum.

[Phoenix A2]

Some basic checks to be done in order that the gear selector can work (which may have been done already):

 

1.) If hydraulic hoses (mounting bracket) have been disconnected from the hydraulic pump unit during repair work, then carfully check that the screwed mounting bracket with the 3 hoses fits parallel and close to the pump (only small gap of about 2-3mm is allowed)

Check also where the hydraulic hoses are placed inside the mounting bracket. The colors of the hoses should be in the folowing order: blue, gold, silver

2.) Check connected hoses on the gear selector:  silver top and blue bottom

3.) During basis setting check if the rear lights get activcated (rear gear is engaged then) between step 5 and 8. If not it could be due to swapped eletrical connectors on the gear selector.

 

See also the comprehensive wiki articles about gear selector, basis setting and hydraulic pump unit (online translation may help with the language):

Gangsteller

Getriebe-Grundeinstellung

Hydraulikeinheit

[Mankmil]

vor einer Stunde schrieb mrbizzy:

I tried to switch places the upper solenoid plugs N286 and N287 still not pushing downwards. Then unplugging one of the lower ones N285 then no gear selection happens at all. The diagnostic reports equal Ampers for both N284 and N285 solenoids.

 

When you ensured, that there could be something wrong with the Control-Unit, check it for broken resistors. It might looks like that:

 

 

These shunt resistors are responsible for current measurement of the solenoids. If one ore more are broken, the current for the solenoid seems to be okay (for the CU) but it isn't due to the broken resistors.

You'll see it immediately, when you open the CU.

[Phoenix A2]

vor 1 Stunde schrieb mrbizzy:

And if you know, is one of those 4 solenoids responsible for down-push movement? if you know, please share.

 

N286, N287 => gear shifting gate selection (turning gear selector shaft of gearbox), feedback to control unit is given by potentiometer G240

N284,N285 => gear selection (pushing or pulling gear selector shaft into/out of gearbox), feedback to control unit is given by potentiometer G239

 

[mrbizzy]

thank you for responding.

i am certain that the hoses are connected fine because the gear lever is being pulled upwards and pushed in and out so pressure is ok.

Rear light gets activated just fine, but because it is not pushing downwards even 2 times slides into R.

And i already used those WIKI pages before looking for help here.

 

So will have to pay closer attention to N286 and N287. i hope it is one of them gone and not the ECU as i have a few spare solenoids laying around.

I saw that i can test them with resistance, so that will be my tomorrows job then.

[mrbizzy]

Update: So i measured the resistance of all 4 solenoids and they are in check by the WIKI.

Also i did switch places both upper solenoid plugs and test the basic setting and even then gangsteller was only pulling up never pushing down.

So that would lead me to think that all is working except the gangsteller and that should be removed and replaced or repaired.

 

BUT there is one small thing that could be worth noting - the gear selector lever potentiometer when in E or Tiptronic position is reporting that it is actually in T-Mi position, so not a correct reading. i tried to attempt the basic setting while supporting the selector a bit upwards in a steady position, but the gangsteller still was not pushing downwards.

 

It is cold outside, where i work on the car, and if needed will have to remove that gangsteller but before i do that i will wait a bit as maybe there is another thing to check or test before blaming the gangsteller.

 

So if you have ny suggestion please share it with me.

 

 

Bearbeitet 27. Dezember 2019 von mrbizzy

[mrbizzy]

Update2: So i figured out which solenoid is responsible for pushing down and decided to replace it. It took much less time than i anticipated and it was worth it as now it is working correctly and during the basic setting all the gears are shifted in correct order. 

But still getting RTFM 12. i suspect it is because of fail reading from gear select lever potentiometer so will take a look at that one now.

[Phoenix A2]

vor 5 Stunden schrieb mrbizzy:

Update2: So i figured out which solenoid is responsible for pushing down and decided to replace it. It took much less time than i anticipated and it was worth it as now it is working correctly and during the basic setting all the gears are shifted in correct order.

Well done.

Did you use a solenoid valve from another gangsteller or a spare solenoid valve (interesting if there is a source to get those)?

Any defect visible on the old solenoid valve?

 

Zitat

But still getting RTFM 12. i suspect it is because of fail reading from gear select lever potentiometer so will take a look at that one now.

At which point does the basic setting abort? I suspect it is before the instruction "(-) to put the gear select lever in "-"Position?

The failure code is most likely related to the gangsteller (e.g. tolerances of potentiometer G239 and G240 not in spec). Have you already tried to set one of the front wheels free (lift above ground) during basic setting?

 

Regarding gear select lever: You can check the voltages of the corresponding potentiometer G272 (see also this guide)?

I am not sure but think, that you have to look on the voltages of G272 only (measurement block 015 value 01) and cannot rely on the percentage values (measurement block 016 value 01) as these are calculated upon successful basic setting.

 

[Mankmil]

vor 18 Minuten schrieb Phoenix A2:

Did you use a solenoid valve from another gangsteller or a spare solenoid valve (interesting if there is a source to get those)?

Ask Google for "E46 M3 SMG Clutch solenoid" 

 

vor 19 Minuten schrieb Phoenix A2:

Have you already tried to set one of the front wheels free (lift above ground) during basic setting?

I've never solved a problem by doin' this.
Do you see the Rear-Lights in the steps 5-8?

RTFM12 is almost always a problem coming from the gear actuator. Have you followed the instructions that have to be done in the "adjust" step? 

[mrbizzy]

Oh yes, i have 2 spare gangstellers. it was cheaper to buy those complete (used) than to buy the potentiometers on them separately, when i needed them.

Solenoid looked normal. i did not bother to test it when it was replaced already. had to move on.

 

While my A2 was waiting for me to start fixing it again, mouse had gotten in and chewed on the micro switch cables that are in the gear selector, so that for sure was giving errors, now soldered those and seems ok.

BUT the gear selector potentiometer might  be causing problems. as it does show T-MI when it should T-0. so it is out of range. now i did not compare the voltage to the wiki but looked at the textual value in diagnostic.

 

I do not know (yet) if those values are depending on basic setting score or not. Will compare voltage with tables tomorrow.

 

REAR lights in step 5 - working fine!

I do follow the adjustment steps, yes.

Have done basic setting many MANY times and only few of them were success in the past so i am familiar with the procedure.

 

Whole front of the car is off the ground as i was replacing the gearbox. so no need to lift one wheel.

 

Now got to check this, but i was "adjusting" the lower potentiometers angle of arm to sensor tooth on gangsteller. because the measured reading was out of range and i thought that was causing RTFM.  maybe i messed up something there.

 

Should the gear reading in speedo correspond to the real shifted gears during basic setting? sometimes it does not look correct in the dashboard.

Bearbeitet 28. Dezember 2019 von mrbizzy

[Phoenix A2]

vor 20 Stunden schrieb mrbizzy:

Now got to check this, but i was "adjusting" the lower potentiometers angle of arm to sensor tooth on gangsteller. because the measured reading was out of range and i thought that was causing RTFM.  maybe i messed up something there.

 

What was/is your measured reading from G239 for its 2 positions?

If you mean the lower lever of the gangsteller that does gear selection: This lever is mounted correctly if it does not touch the housing of the gangsteller when moved manually from end to end (for this test: unmounted gangsteller or at least the lever not fixed to the gear selector shaft).