Always Overcharged

This is from a well behaving car
[Slip figures on the right]
TC Open 576
TC Open 608
TC Open 608
TC Open 608
TC Open 576
TC Open 608
TC Open 608
TC Open 576
TC Open 576
TC Open 576
TC Open 576
TC Open 608
TC Open 576
TC Open 576
TC Open 576
TC Open 576
TC Open 576
TC Open 576
TC Open 608
TC Open 608
TC Open 1024
TC Open 736
TC Open 736
TC Open 640
TC Open 832
TC Open 832
TC Open 768
Torq.Conv.Reg 352
Torq.Conv.Reg 64
TC Closed 0
Torq.Conv.Reg 0
Torq.Conv.Reg 96
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
Torq.Conv.Reg 0
Torq.Conv.Reg 32
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 256
TC Closed 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 32
Torq.Conv.Reg 32
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
TC Open 160
TC Open 160
TC Open 128
TC Open 64
TC Open 896
TC Open 928
TC Open 672
TC Open 896
Torq.Conv.Reg 576
Torq.Conv.Reg 96
Torq.Conv.Reg 32
TC Closed 0
Torq.Conv.Reg 96
Torq.Conv.Reg 32
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 96
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
Torq.Conv.Reg 0
Torq.Conv.Reg 64
TC Closed 0
TC Closed 0
TC Closed 0
Torq.Conv.Reg 128
Torq.Conv.Reg 96
Torq.Conv.Reg 64
Torq.Conv.Reg 64
Torq.Conv.Reg 128
TC Closed 0
Torq.Conv.Reg 32
Torq.Conv.Reg 160
Torq.Conv.Reg 0
TC Closed 0
Torq.Conv.Reg 96
Torq.Conv.Reg 32
TC Closed 0
Torq.Conv.Reg 0
Torq.Conv.Reg 192
Torq.Conv.Reg 128
Torq.Conv.Reg 0
Torq.Conv.Reg 192
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
Torq.Conv.Reg 96
Torq.Conv.Reg 32
Torq.Conv.Reg 64
Torq.Conv.Reg 64
Torq.Conv.Reg 64
Torq.Conv.Reg 64
Torq.Conv.Reg 64
Torq.Conv.Reg 96
Torq.Conv.Reg 64
Torq.Conv.Reg 64
Torq.Conv.Reg 96
Torq.Conv.Reg 128
Torq.Conv.Reg 32
Torq.Conv.Reg 0
Torq.Conv.Reg 32
Torq.Conv.Reg 32
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
TC Open 64
TC Open 128
TC Open 0
TC Open 32
TC Open 0
TC Open 160
TC Open 288
TC Open 576
TC Open 608
TC Open 608
TC Open 576
TC Open 608
TC Open 608
TC Open 576
TC Open 576
TC Open 576
TC Open 608
TC Open 576
TC Open 576
TC Open 576
TC Open 576
TC Open 608
TC Open 576
TC Open 608
TC Open 608
TC Open 576
TC Open 608
TC Open 608
TC Open 608
TC Open 608
TC Open 608
TC Open 608
TC Open 608
TC Open 608
TC Open 608
TC Open 576
TC Open 608
TC Open 608
TC Open 608
TC Open 608
TC Open 608
TC Open 576
TC Open 608
TC Open 1088
TC Open 608
TC Open 704
TC Open 320
TC Open 512
TC Open 672
Torq.Conv.Reg 512
Torq.Conv.Reg 32
TC Closed 0
TC Closed 0
Torq.Conv.Reg 0
Torq.Conv.Reg 96
TC Closed 0
TC Closed 0
TC Closed 0
TC Closed 0
Torq.Conv.Reg 32
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
TC Closed 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
TC Open 128
TC Open 32
TC Open 96
TC Open 128
TC Open 256
TC Open 544
TC Open 576
TC Open 608
TC Open 608
TC Open 608
TC Open 608
TC Open 608
TC Open 608
TC Open 608
TC Open 608
TC Open 608
TC Open 576
TC Open 608
TC Open 608
TC Open 608
TC Open 608
TC Open 608
TC Open 608

This above is what a healthy trans should look like noting that 0-128 is the spec figure for slip while in TCC [fluctuations out of spec I think are acceptable just on lock up and release but not random during TCC mode as in the logs below.

Bad behaviour
TC Closed 0
TC Closed 0
TC Closed 0
Torq.Conv.Reg 64
Torq.Conv.Reg 0
Torq.Conv.Reg 256 BAD
Torq.Conv.Reg 352
Torq.Conv.Reg 384
Torq.Conv.Reg 384
Torq.Conv.Reg 416
Torq.Conv.Reg 416
Torq.Conv.Reg 448
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 0
Torq.Conv.Reg 64
Torq.Conv.Reg 96
Torq.Conv.Reg 96
Torq.Conv.Reg 128
Torq.Conv.Reg 96
Torq.Conv.Reg 32
Torq.Conv.Reg 160
Torq.Conv.Reg 160
Torq.Conv.Reg 128
Torq.Conv.Reg 96
Torq.Conv.Reg 288
Torq.Conv.Reg 224
TC Closed 0
TC Closed 0

PaulW

I asked Gabor about the whole thing, but I really don't want to disclose what he did (he didn't tell me everything) because it's his mod.

I too stated that I will be interested to see if it learns.....but after looking again at logs, it does not appear that the current to the TC solenoid valve changes at all during regulating. It's either at the regulating amount or it's at the open amount, or locked amount.

It's the same on all A8's, and the regulating solenoid current doesn't change due to conditions, it's just a constant number.

Gabor explained what is going on in the valve body, and it sure makes sense to me, seeing how mine stopped working correctly one day (by starting TC dropout). However, I'm not going to give his secrets away.

I will report if the TC dropout comes back, but my gut feel is that it won't.

tonypai

I bet it would, but where do you get one?

CalG

AOC

I might come to another observation regarding these two logs. The first one looks entirely similar to many that might be taken from my car. The particular aspect of data that may be characteristic of "hunting" is the single point excursions from zero slip to some value, then back to zero by the next captured data point. The greater the momentary value, the more observable and objectionable the performance.
A shortfall in sophistication.

Definition: <hunting> repeating short duration changes of engine RPM due to momentary loss of friction control of the TCC, characterized by slip initiaton and overcompensation through the N218 PWM solenoid control current.

I will like to see a log of group 7 during a "thump" event. It may be the same as hunting only on the over run.

Regards

CalG

Always Overcharged

first log it is a whopping 400 and something at one point and is nowhere near lock up so this will cause a surge/drop in rpm.
There will be some huge forces at work so the temp excursions around lockup and release are probably litteraly a spin off.
The thump is I think the momentary and very short term large excursions and probably yes more likely felt more in overrun.
That said the manuals dont seem to rate any issue during overrun conditions so slip in overrun can possibly be ignored.

CalG

This looks pertainent

mining!

CalG<ul><li><a href="http://www.wipo.int/pctdb/en/wo.jsp?IA=EP1998006315&amp;DISPLAY=DOCS">http://www.wipo.int/pctdb/en/wo.jsp?IA=EP1998006315&amp;DISPLAY=DOCS</a</li></ul>

ttuling

... and that bodes well for it continuing to work like it does now (unless the regulating current is already pegged to a low limit that is subject to long-term adaptation).

I look forward to hearing what Gabor uncovered which led to this particular modification, and whether he thinks a little hunting remains because it was not possible to completely repair the identified problem, or (hopefully not) because the modification masks other things which are harder to identify or fix. And if the purpose of ZF's late-1999 modification is now understood, that would be interesting to hear about too!

Tom

CalG

This is a very eye opening paper on a single aspect of the operation and controls for the TCC . There are some important topics that may point us to better understanding. I must reread to better get my head around all that here.
Perhaps it is not even part of these Pre 2000 TCU's.

CalG<ul><li><a href="http://www.patentstorm.us/patents/6073740-description.html">http://www.patentstorm.us/patents/6073740-description.html</a</li></ul>

CalG

Tony

Just ordered one ! Not new, but from a '01 FUN series transmission.
$500 From a ZF authorized rebuilder.

It'll be a while before it's in though. We are supposed to get 6-9 inches of snow starting tomorrow night.

CalG

Always Overcharged

P CT WORLD-WIDE ORGANIZATION FUR Intemationales Buro INTERNATIONAL REGISTRATION VEROFFENTLICHT AFTER the CONTRACT UBER the INTERNATIONAL COOPERATION IN the AREA of the PATENTING (PCT) (51) international patent classification 6: (72) inventor; and (75) inventor/applicant (only fiAr US): CARPENTER, Bernd [ TM Eschle 7, D-896 10 Oberdischingen (DE). (74) common representative: ZF FRIEDRICHSHAFEN AG; D-88038 Friedrichshafen (DE). (43) international publication date: 22. April 1999 (22.04.99 (81) regulation states: JP, KR, US, europaisches patent (RK, CH, CY, DE, DK, IT, F FR, GB, GR, IE, IT, LU, MC, NL, PT, SE). Published With international search report. Before expiration derjhr and run gene one the requirement certified period; VerOffentlichung repeated if and run gene one to arrive. (54) Title: METHOD FOR ADAPTING A TORQUES CONVERTER LOCK UP CLUTCH (54) designation: PROCEDURE FOR the ADAPTATION of a WANDLERUBERBRUCKUNGSKUPPLUNG (57) Abstract The invention relates ton of A method into which application pressure is adapted for A torques converter LOCK UP on clutch (7). To tons this end, within A roofridge interval, A pressure CHANGES is output after A transition function and the existence OF the reaction OF the torque converter LOCK UP clutch is tested after output OF the application pressure during on application phase from at electronics gearbox control (13). During A non existing reaction, additional intervals acres then outputs. The application phase is then completed when the reaction OF the torque converter LOCK UP clutch occurs.
The control/regulating phase for the torques converter LOCK UP clutch (7) follows after completion OF the application phase. (57) summary for a Wandleruberbrtickungskupplung (7) is suggested to em procedure, with which em putting on pressure one adapts. For this after from gift of the putting on pressure during a putting on phase of an electronic transmission price increase (13) innerhaib a first interval a DrUckanderung is spent after a Ubergangsfunktion and the presence of the reaction of the WandlerUberbrueckungskupplung is gepruft. With missing reaction further intervals are then spent. The putting on phase is terminated if the reaction of the Wandleruberbruckungskupplung occurs. After end the tax/rule phase for the transducer clutch (7) follows the putting on phase. F16H 61114 (21) international file reference: (11) international publication number: WHERE 99/19645 (22) international date of registration: 5. October 1998 (05.10.98) PCT/EP98/063 15 (30) priority data: 197 44 697,3 10 October 1997 (10.10.97) DE (71) applicant (for all regulation states except US): ZF FRIEDRICHSHAFEN AG [ D-88038 Friedrichshafen (DE). DN B p t7 t 1(1) 1(2) II i l tOti t2t3 t4t5t6 t7 t