robertsonse

Dear Folks,

Ever since at my request a friend fumbled with the Instruments (17) adaptation channels using VAG-COM to reset the oil intervals, my 1998 B5 A4 1.8T Quattro Sedan AEB engine, has gotten into the annoying habit of resetting all of the computer readings (mileage avg, speed avg, etc) in the most random fashion. Sometimes it takes 3 or four days, some other times, in less than 1 hour just on two or three ignition key moves. In any case the acumulated trip mileage never seems to reach 200 km without a reset. Whenever the random reset takes place it always happens when turning the key to the right (a slightly audible "click" can always be heard when the whole thing resets), without having to even start the engine for this to happen.

Before this happened, I would always go about without getting a reset until I wished to do so manually (for example after filling up).

We have tried writing a "1" value to channel 00 in order to reset everything to factory values but without success (there is no option to write a "0" value" there).

This car model does not have the trip1 trip2 system, as pressing on the underside of the wiper stalk only manages to turn display on/off, and keeping it pressed for a second manually resets all the values.

We are now desperate as to how to get the old "behaviour" back. Can provide actual readings for every instrument adaption channel if needed.

Any help from the experts is appreciated.

Thank you all in advance

robertsonse

I believe I have narrowed down the problem to channel 00 not showing any stored values ever. No matter if we try to save a "1" value, or a "0" value to reset channel 00 to factory default values, the darned channel keeps reading "__ __", so I believe no value is effectively saved by VAG-Com. Any suggestions on how to proceed most appreciated.

robertsonse

Here are the values read by VAG-Com on all the Instruments/Adaption channels:

**This is the full list of all available channels from 00 to 99. Channels not shown below simply read as “NOT AVAILABLE”, eg. Channel 1.

Ch 00 Stored Value Can/cannot seem to be able to modify it

00 (__ __) always reads (__ __) no matter what
Prompts to save 1 or 0 values depending on previous state, but does not seem to change stored value

02 0 cannot be modified unless previous value 1

03 100 cannot be modified

04 1 accepts only 1,2,3,4,5,6 values

05 15 can be modified

06 30 can be modified

07 36 can be modified

09 27162 (odometer cumulative total x10 in km) -cannot be modified

10 5 can be modified

11 30 can be modified

12 36 can be modified

21 4 cannot be modified

30 128 cannot be modified

35 0 cannot be modified

It must be channels 00 or/and 35 which are the culprit but they don’t let themselves be modified (unless there is a specific sequence or cross-channel value combination that does the trick).

robertsonse

No-one chiming in? Is this what this forum has come up to?

JulianHicks

OK, let me 'chime in'

If you have VCDS,

1) what does the Autoscan of Ecu 17, the Instrument Panel look like?
2) what does the output from an SRI reset / cancel look like?

Julian

robertsonse

Hello Julian,

Thank you so much for your reply.

Unfortunately the only vagcom we have is old version 3.11.

JulianHicks

I guess you don't need me to warn you of the perils of trying to use obsolete software - in this case, 13 years old!

The panel counts and adaption channel values of Audis all seem to be different; I worked out what mine was doing [A8] by scanning the channels several weeks apart to see which numbers changed and which were fixed. As I don't have access to an A4 of that era I can only offer comments and suggestions:

1) You normally need to 'logon' to panels to change them correctly; my assumption is that VCDS [VAG-COM] knows these and uses them without informing you.
2) I didn't think you could change channel 0 - maybe I'm wrong.
3) Not all the channels are related to the same thing; most are related to service intervals. I'm not sure how the trip computer uses them.
4) It's not too clear which problem you're trying to fix. Is it service intervals or trip computer?

By the way; this is what I think your numbers mean:

A02,Service Reminder = 00 : Service not required [01=oil service due;10=inspection service due;11=oil and inspection service due]
A03,Consumption Correction = 100 : ??
A04,Language = 1 : German
A05,Maximum Distance to Oil Service (OEL) = 15 : 15,000 km
A06,Maximum Distance to Inspection (IN1) = 30 : 30,000 km
A07,Maximum Time to Inspection (IN2) = 36 : 360 days
A09,Odometer = 27162 : 271,620 km
A10,Distance to Oil Service (OEL) = 5 : 5,000 km
A11,Distance to Inspection (IN1) = 30 : 30,000 km
A12,Time to Inspection (IN2) = 36 : 360 days
A21,Immobilizer = 4 : ???
A30,Fuel Level Sensor = 128 : ???
A35,Speed Threshold - Oil pressure system = 0 : ???

There's some funny values in there ...

Julian


Note: It's very helpful if you indicate where you come from in your profile

robertsonse

Hi again Julian,

I truly appreciate your well-written and detailed answer.

Yes, old is the word, and I am ever so grateful to this car because it has aged so well together with me.

In vcom ver. 3.11 you select an icon named "17 Instruments", and once there, another one that reads "10 Adaptation", so I guess VCDS is an entirely different way of working on the same car channels. I seem to remember having read somewhere that channel 00 could somehow be "reset" so that the rest of the channels were automatically set to default "factory values", which the SRI Reset that you mention is probably short of. Trouble is I don't know how to go about this or even whether this would solve my problem.

I think you are totally right on what my numbers mean as they would make perfect sense to me.

To elaborate on the problem I have, whenever a random reset takes place it works two-fold:

a) The partial odometer is automatically set to 0.0 km.
b) The trip computer cumulative values, namely "time driven", "average consumption", "average speed", and "mileage left" are also reset in turn.

I do not really worry much about the average speed or time driven, but the rest of the values I find very informative.

Thanks once again for taking the trouble, especially as you have an A8, which by the way must be a wonderful machine :-)

JulianHicks

: You've made me realise that I don't understand how the trip computer derives its values. I've never used my trip computer in the 9 years I've had my A8; my display is left on 'How many miles before I run out of fuel' so I've never worried about the rest of the data or 'mucked around' with the reset stalk.

: I'm not sure how 'fumbling' with the Instrument panel's settings has upset the trip computer as there's no obvious settings in the panel that affect the trip figures.

: 'Vag Com Diagnostic Software' [VCDS] IS VAG-COM; the name was changed some years ago to avoid litigation from the VW Audi Group [VAG] over misuse of 'VAG'. Accordingly, your description of the use of the old Vag-Com is the same as the product in use today [Version 17.1].

: VCDS has an 'SRI reset' option. It shows the current panel values [that is, the adapation channels used for service data] and optionally allows you to reset it/them. Do you not have the SRI Reset function? [The advantage is that you don't have to play with the channels; the 'Reset' option resets the right ones].

: I presumed you'd have an 'Autoscan' function in VAG-Com, even at that version. I was expecting to see what info came out of your ECU 17. This is the edited Autoscan of my A8 to show the panel information.

Address 17: Instruments Labels: User\4E0-910-xxx-17.lbl
Part No SW: 4E0 910 950 F HW: 4E0 920 950 F
Component: KOMBIINSTR. VDO H49 0200
Revision: D03 Serial number: AUDID3DN000886
Coding: 0000418
Shop #: WSC 00028 210 01865

: My research indicates that saving to ECUs Adaptation Channel 00 does reset it to default, but only in ECUs that support it. Even if the A4 panel does, you may have to supply the 'login' code to allow that to happen.

: What is the VIN of your A4? Which country are you in?

: Are you sure you haven't got a panel issue or a low voltage problem? Have you scanned it with VAG-Com?

: I have an old A8 with 227,00 miles on the odometer. Still goes well though ...

Julian

robertsonse

Hi Julian,

Please forgive my delay - I've been away from my laptop for a good week.

According to the owner's manual the mileage left is calculated upon avg consumption of the last 30 km.

I am dumbfounded myself as to how fumbling with Vag-Com has caused this erratic trip computer resets, but it somehow has.

We don't have a RSI function in ver 3.11, but the most regrettable thing is I later realized that interval reminders can be reset with a sequence involving the trip reset stalk and the clock one. It says so in the owner's manual, and I tried and it certainly does its job.

Yes, there is a fault code scan function in ver 3.11, which incidentally came clean - see the pictures attached, which also show the ECU 17 reference.

I am an expat living in Spain, and I was never given a VIN number. All I know is it is a March 1998 A4 B5 1.8TQ 5speed manual AEB engine, and the rest of the car runs like a charm - just had to replace control arms, wheel bearings, steering tie rods, dampers, pads, rotors, and the usual oil+filter and timing tensors and belts as per maintenance schedules).

Voltage is always ok, and since this started happening right after using Vag-Com to reset intervals and the instrument panel does not throw any codes, it is all really weird.

Yes, the A8 must be a pretty impressive machine.

Take good care and thank you once again