1.2tdi 3L transmission problems

Ruud95

Ruud95

New Member
Transmission problems. Any advice is welcomed!

Hey guys, 1.2tdi 3L 2001. owner here.

I have run into some transmission problems. I was overtaking a car on the road and the Lupo performed kick down from gear 4 to gear 3, and seamed ir chuld not find the gear. The gears in the panel flashed between each other and the car went into SAFETY MODE?
I can turn on the engine but the accelerator pedal is unresponsive. And the lights by gears stick are flashing "+" "-" "D" "N" both when in tiptronic or automatic.
When turning ignition but not starting engine, switching gears in tiptronic mode shows in dashboard but i can hear that the car is not switching gears.

My friend pulled me home from midle of road.

Assessments:

VCDS shows:
01605 Potentiometer 2 for gear recognition (G240)

Basic setting stops after the 28 step shifts and writes RTFM! with same error
(First time I have done basic settings for the car)

Checked wiering from potentiometer 2 to gerbox ECU with beeping tester, all 3 wires test oky.

Gear selector rod has small movment in top ball head

Prior to incident Pressure Accumulator made 6 gear changes before starting the pump. Oil level is good.

History:
Before this incident, the car already had a faulty 5 gear, first 4 gears worked perfectly fine but when switched into 5th, the car in couple secs went into safety mode. Afrer switching ignition off and on chuld use first 4 gear perfectly fine again but not the 5th.

Mechanics in my area doesn't understand the 1.2 3l transmission, so i only used the first 4 gears but now the car doesn't work so I will try to figure the problem out myself.

Any advice on what else shuld i test or what chuld be the problem?

Faulty top potentiometer is the obvious answer but do they break and how can I test it befor paying the €€€

Whuld switching potentiometer 1 and 2 with places resort in the error code changing from g240 to g239?
 
the advice on the GGE page on the German Wiki is valid. A GGE should be done every 30kkm.

The specific instructions in German are here: https://wiki.a2-freun.de/wiki/index.php/Getriebegrundeinstellung

It also explains what might be wrong on each step, specifically RTFM 12. You will need to measure the potentiometer values and see how stable they are (dirty tracks may cause this kind of thing).
You may also want to post on the German forum (a2-freun.de) - there is an English subforum there.

- Bret
 
My first step would be to change the potentiometer. When I bought my A2, unbeknown to me, it had a partially stripped fifth gear, probably caused by an incomplete shift due to a failing accumulator. It soldiered on for another five years until failing completely. The good news is that fifth gear is accessible without removing the gearbox. However, if it is a broken fifth gear, dismantling would be preferred to remove the debris but you can inspect beforehand.

RAB
 
Last edited by a moderator:
bretti_kivi said:
the advice on the GGE page on the German Wiki is valid. A GGE should be done every 30kkm.

The specific instructions in German are here: https://wiki.a2-freun.de/wiki/index.php/Getriebegrundeinstellung

It also explains what might be wrong on each step, specifically RTFM 12. You will need to measure the potentiometer values and see how stable they are (dirty tracks may cause this kind of thing).
You may also want to post on the German forum (a2-freun.de) - there is an English subforum there.

- Bret
Click to expand...
Thanks for reply, great information!
 
RAB said:
My first step would be to change the potentiometer. When I bought my A2, unbeknown to me, it had a partially stripped fifth gear, probably caused by an incomplete shift due to a failing accumulator. It soldiered on for another five years until failing completely. The good news is that fifth gear is accessible without removing the gearbox. However, if it is a broken fifth gear, dismantling would be preferred to remove the debris but you can inspect beforehand.

RAB
Click to expand...
Thanks for reply! You are the expert on this RAB! Always find your responses great in 1.2tdi 3l forums!

Whuld switching top and bottom potentiometers result in error changing from G240 to G239? That whuld be great way to certify if the potentiometer if faulty.
Also i cannot finish basic setting before fixing the g240 error right? And the car will stay it Safety mode (can start the engine but no accelerator response) only if I can successfully finish the basic setting right?

Is it also possible that gear selector forks 3/4 are broken, would that resort in car going into safety mode?
 
maxufeiss said:
Maybe just swapping connectors between them is doable for quick test?
Would not turn on engine like that, but for test should not be a problem.
Click to expand...
Good idea. Not sure if the wrong readings chuld still resort in error codes, becouse if the top contractor is connected to bottom potentiometer, the readings of the switching rod position whuld be wrong no?
 
Switching the pots should show that the pot is at fault - they are identical. If there's any fault, you won't be able to complete the basic setting. It could be a fork but wouldn't that affect fourth as well? Forks are known to fail because of faulty welding.

RAB
 
If they are easy enough to swap, then that's better ofc. Have you tried reading their voltage values from gearbox, group 15, zones 3 and 4?
0V, 5V or 12V at any time might indicate problem.
 
RAB said:
Switching the pots should show that the pot is at fault - they are identical. If there's any fault, you won't be able to complete the basic setting. It could be a fork but wouldn't that affect fourth as well? Forks are known to fail because of faulty welding.

RAB
Click to expand...

Hey, again. So I swapped the potenciometrs with each other and the error code went from G240 to G239, so the potentiometer was definitely faulty. I changed it with a new one and now i have no errors in gearbox VCDS.
But still my car won't switch into Drive/Reverse or tiptronic.
But now i can rev the engine in neutral gear, the accelerator pedal is responding now but only in neutral. Car wont go into gears.
And the "D";"R" ; "+/-" symbols next to gear shift stick are flashing.
Is the car still in Safety mode, and how can I get out of it if the error codes are fixed?
 
Have carried out the basic settings check Bretti suggested after replacing bad potentiometer?

“the advice on the GGE page on the German Wiki is valid. A GGE should be done every 30kkm.

The specific instructions in German are here: https://wiki.a2-freun.de/wiki/index.php/Getriebegrundeinstellung

It also explains what might be wrong on each step, specifically RTFM 12. You will need to measure the potentiometer values and see how stable they are (dirty tracks may cause this kind of thing).”
 
You must log in or register to reply here.
Back
Top