OBD blink codes on an Audi 80 B4 2.0E

[RichardV]

Does anyone have experience of successfully reading OBD blink codes on an Audi 80 2.0E?

I have a 1993 Audi 80 2.0E and I am having difficulty getting diagnostics.
The car has pre OBD2 connectors.
One black, labelled + & -
One white, labelled L & K

I have found instructions for getting the codes for similar aged cars (1989 Audi 80 Quattro) which have the same connectors, but these do not seem to work on my vehicle, (lights don’t flash at all). There is also no provision for using a link or fuse in the fuel pump relay which is suggested for some pre OBD2 cars. Any help or suggestions would be much appreciated.

Thanks in advance!

Richard V


These are the instructions I found for a 1989 Audi 80 Quattro with identical connections to mine.


Turn ignition on. Engine warning light (on instrument panel) should come on. Start engine. Engine warning light should go off. Drive vehicle for at least 5 minutes to store necessary information in control unit memory.

During test drive, accelerate engine above 3000 RPM and briefly accelerate using full throttle. DO NOT turn ignition off as this will erase control unit memory. If engine will not start, crank starter for at least 5 seconds.

Return ignition key to "ON" position. Fault codes may now be read.

1. Locate 2 diagnostic connectors in drivers foot-well area or in fuse-box. Connect a test light between connectors “+” on A and “L” on B. (see attached jpg)

2. Connect a jumper wire to “-“ on A. Touch other end of jumper wire to “L” in connector B for at least 4 seconds. Fault codes will now be displayed by a flashing the bulb.

3. Trouble codes will then be flashed as 4 digit numbers. After each flash there will be a 1/2 second pause before the next flash occurs. Adding flashes together will obtain each code digit.

4. To advance to next fault code, touch end of jumper wire to the only terminal in connector B for at least 4 seconds. See Fig. 1 . After each digit code is flashed, there will be a 2 1/2 second pause. After fourth digit of number is flashed, a 2 1/2 second pause will follow before the fault code is repeated.

5. The fault code will be repeated until the ignition is turned off. Record fault code. Check the list of input codes and possible problems.

CIS DIGITAL CONTROL INPUT FAULT CODE IDENTIFICATION CHART
Code System Affected Probable Cause
1111 Control Unit Defective Memory Circuits
2111 Speed Sensor Control Unit Not Receiving Signal (1)
2112 Reference Sensor Control Unit Not Receiving Signal (2)
2221 Control Unit Pressure Sensor Vacuum Hose Leak/Plugged
2222 Control Unit Pressure Sensor Defective Pressure Sensor
2141 Knock Regulatio Engine Or Ignition Knock (3)
2142 Knock Sensor Defective Sensor Or Sensor Wiring
2123 Full Throttle Switch Faulty Switch Or Wiring Problem
2121 Idle Switch Faulty Switch Or Wiring Problem
2312 Coolant Temp Sensor Or Sensor Wiring Defective
2322 Intake Air Temp Sensor Or Wiring Defective
2342 Oxygen Sensor Sensor Or Sensor Wiring Defective
4444 No Faults Have Been Recorded
0000 End Of Diagnosis (4)

(1) Another cause could be a misadjusted distributor.
(2) Another cause could be signal is out of phase (misadjusted distributor).
(3) This would cause ignition timing to be retarded the maximum amount.
(4) This code is indicated by the light staying off for approximately 15 seconds after the start signal.

[John.]

Do you have a working "engine management light" on the dash? The system might need the warning light circuit to be complete for retrieval of faults via blink codes?

Mikes2(on here) has good knowledge of this type of thing, hopefully he'll have the answer.

[RichardV]

Thanks for getting back to me.

The car does not have an engine warning light. The little circuit shown in the jpg attached to the original posting has a test bulb included between the + (12V) and the L line and my understanding from the notes was that this should flash the blink codes when the OBD is activated.

I have attached the jpg showing the circuit that was recommended.

[mikes2]

Are the connectors in your fusebox ?

There's normally 3 on the later cars - black, white and blue.

[RichardV]

They are in the fuse-box but there are only two. One black (+ & -) and one white (K & L) I have seen references to a third blue connector but there is no sign of that in my car.

[mikes2]

Are you getting 12v in the black connector ?

[RichardV]

Yes, when I take the L line to 0V (-) with the jumper, the bulb lights, so there is voltage on +

[mikes2]

Wonder if the digifant ecu is not capable of sending out blink codes.

Pretty sure I've had vcds running on an ABK many years ago so you can pull errors - just not using the blink method.

Meantime, I've uploaded some wiring diagrams for the ABK here

http://s2-audi.co.uk/workshop/schematics_abk/abk.htm

[RichardV]

Ok, that makes sense. I'll have a look at the VCDS cables and software. Thanks!

[RichardV]

Thanks! I now have that working with the VCDS software and cables.

I now have a bunch of error codes to follow up on!