01N auto box problems

[expat2000]

Hi All


New problem with the old banger.
Its a 1998 A4 B5 1.9 TDI with the 01N 4-speed auto box 275k km on the clock


Starting last week it seemed reluctant to select 4th when driving along then more and more reluctant to change gears at all. Not selecting 1st when stationary, not selecting 4th when cruising around 50mph.


Did some research and seemed to be pointing at the speed sensor(s) on the box but couldn't get it on VCDS until yesterday. (I only use the car weekends and occasionally during the week)


VCDS says its the solenoid valves, more reading on hear and other sites are pointing to a wiring problem rather than solenoid problems.



So car up on stands, find the multipin connector at the back of the box, after much swearing it comes apart, seems a bit damp inside, give it a clean out with tissue paper and a good squirt of water dispersant, dry it out again and pop it all back together. Start car, clear fault codes, run it through the gears on the slector, no faults reappear, Huzzah!!


Use the car last night, runs great, smug face engaged!


Take significant other to the docs this morning, same old problems again!!!!


So suggestions?


I think I am on the right lines with wiring but any ideas on likely source much appreciated. I thought the multipin plug was most likely as it sits exposed on the back of the box but digging into pictures at lunchtime and spares on ebay the printed circuit strip inside the box can fail? Or the cabling from the multipin plug to the rest of the loom looks very brittle and has some wicked kinks in it, a possible source of problems?


To be honest even if its corrosion in the multipin connector I cannot see how to clean it properly as its in a awkward place and very small. Imagine a 15 pin trailer power connector thats about 12mm in diameter.


Advice on the next step would be great, thanks.


Also struggling to find the part number for it as partbase says "round connector housing; no replacement part; 4-speed; automatic" Item 26 on this page
AUDI A4/AVANT [A4] (EUROPE) 1998: ELECTRICS: 97216. WIRING HARNESS FOR; AUTOMATIC GEARBOX; ADAPTER CABLE LOOM; FOR SPEED SENSOR

[expat2000]

OK so update....

no time or inclination to do anything until the weekend but trawling the net for possible problem areas and replacement parts and I came across a gearbox ECU reset procedure on a Golf TDi forum and its easy and cheap i though got to be worth a go. Normally used when changing any setup of the engine as it clears the 'learned' characteristics of the gearbox and sets everything back to default settings.

So tried it and voila, problem appears to be completely solved. Have been out for two days in the car and no problems (including one drive in the pouring rain), changes where it should up and down and no drama. Settings definitely changed as it seems to hang onto first much longer before changing but don't care as it works!!

I think there was a connection problem that had been getting worse gradually so the gearbox had perhaps learned to work around it. Not sure bit of speculation but seems to have sorted it. Will keep you posted if the problem reappears but here is the gearbox reset procedure in case anyone needs it for future reference (nicked from a golf TDi forum but not sure which one):

1.key on (dont start, just turn the car on)
2.gas down to floor for 10 sec
3.while holding gas, turn key off
4.let go of gas
5.key on (again, on, dont start) for 5 min (for throttle readaptation). touch nothing.
6.then start while touching nothing.
7.drive and see what happens.
its not uncommon to have to do this over and over, because u make small changes and forget to reset yet again. i cant count the # of posts where people change 99 things and reset 99 times, only to make one last change, forget the final reset, then give up and shoot the car with a shotgun. so for those that missed it *always reset last!*
This method is not needed for the 3speed 010, as that has no tcu and yes, this reset can be done thru vagcom too!
final note. i have done this method so many times for all my auto 4speeds, and it works everytime! if it doesnt, there is another issue that needs solving. hence, begin solving all issues my reset (easy, free, 5min). then, if needed, go to vagcom. after changes, reset. and so on until everything works perfectly. refer to my other post about solenoids and other DIYs about valve body cleaning and other issues. dont give up folks!!! usually its simple stuff to fix it.

Additionally, this is intended to complement a TBA (throttle body adaptation) performed in vcds/vagcom, not replace it. In any car, this will reset the transmission relationship with the TB, not necessarily reset the TB itself. That can only be done electronically with vcds (usually group 60 in basic settings).


edit: Works on all vw 4/5/6 speed auto transmissions from 1988 with the 096 corrado to present. I haven't confirmed DSG, but I'm 99% positive it will work. i have confirmed this method works for the 5 and 6speed tiptronics also. i have (had) a mk5 jetta, b5 passat and a b5 and b7 a4, and it works on all of these cars! I do this every gas fill-up.

[Juan Manuel]

Hello Expat2000, I think you are the first to have same car as me, A4 B5 TDI with old 4 gear auto box.
Really I couldn''t ffind any information before finding your post. I didn't know even its name is 01N !!!! Thank you so much.

I have a problem with the auto box, I think is pretty similar to yours, putting it in D, it never uses 1st gear... it uses 2nd from start onto approx 75 Km/h (3200 RPM), then changes into 3rd... and never gets into 4th.

I'm trying the reset you described here and see whats happens.
Any other suggestions ?

Thank you again

[Noony]

Just a quick question have either of you had fluid and filters changed? I know Audi say they are sealed for life but I had mine changed and it makes the world of difference.

[expat2000]

Hello Expat2000, I think you are the first to have same car as me, A4 B5 TDI with old 4 gear auto box.
Really I couldn''t ffind any information before finding your post. I didn't know even its name is 01N !!!! Thank you so much.

I have a problem with the auto box, I think is pretty similar to yours, putting it in D, it never uses 1st gear... it uses 2nd from start onto approx 75 Km/h (3200 RPM), then changes into 3rd... and never gets into 4th.

I'm trying the reset you described here and see whats happens.
Any other suggestions ?

Thank you again

Hi

Thread from the dead!
I think you're right that the TDi with the 4-speed auto is a rare combo.

I'm struggling to remember what happened after this as I sold my Audi about 3 years ago. I can't recall if thsi was before or after my major gearbox problem, the radiatior sprung a leak and coolant mixed with the gearbox oil so I ended up doing a filter and oil change after I had replaced the radiator and coolant. As the other poster says it makes a world of difference to the gearbox so if your car is a high miler then I'd recommend doing it. It's not that difficult just takes a while (and is messy) as getting the correct level when the gearbox is at the correct operating temperature is critical.

As I recall I think the reset sorted most of my probelms at the time. The car eventually gave up when the big wheel between the engine and gearbox (like a flywheel but its not called that on auto boxes) started to come apart. Major PITA to change (and it's specific to the engine/gearbox combination) so scrapped the car at that point.

Hope that helps.

Stuart

[Juan Manuel]

Dear Noony, you are right, Audi seems to think that the fluid is for life... but I think Audi never thought we are still driving 1998 models
I changed the fluid. At first only a liter came out when we loosen the oil plug down in the gearbox. Then we put some compressed air from the upper plug (where you put new oil), and I think a total of 4 liters came out.
We refilled with 4 liters and for the moment the car stays as it were before. In the weekend I will have the VAGCOM and I''ll clear all the fault codes that could appear and then I'll reset the gearbox and look what it happens
Do you have same car as expat2000 and me?

[Juan Manuel]

Thank you Stuart for answering so fast, even iff you do not have the Audi no more.
I really like the TDI - 4 trans combo, it's sweet to drive and low diesel consumption also.
Mine has 261.000 Kms (about 163.000 miles), I think it has some life onto it (I hope so!!!)
I'll try to look at the oil level wile looking at the temperature on the VAGCOM. At this point the level must be at top right ?

Please explain me what is Major PITA ?

Thank you again and best regards