90 90 no fault codes.

[Mark Rutherford]

Fuse 21 is good.  I think it provided power to the diagnostic connector.  I
have 12 volts at the connector, and a good ground on the other pin.
Grounding the ECU wire results in the check engine light, and a LED
connected between the 12 volt pin and the ECU pin coming on.  When removing
the ground it should begin the blink code sequence, some code if there is a
problem or 4444 if there is no problem.  In my case the check engine light
and the LED go out but nothing else happens.



-----Original Message-----
From: quattro-bounces at audifans.com [mailto:quattro-bounces at audifans.com] On
Behalf Of Al S
Sent: Monday, April 19, 2010 4:53 PM
To: Mark Rutherford; 'pdooley'; 'Quattro List'
Subject: RE: 90 90 no fault codes.

Check fuse #21 in the engine compartment.

-----Original Message-----
From: quattro-bounces at audifans.com
[mailto:quattro-bounces at audifans.com]On Behalf Of Mark Rutherford
Sent: Monday, April 19, 2010 1:57 AM
To: 'pdooley'; 'Quattro List'
Subject: RE: 90 90 no fault codes.


Very possible, I have found and repaired 2 large leaks.  The hesitation
started after these repairs.  The issue of no response from the ECU in
diagnostic mode has me concerned.  I would like to see a 4444 code to ensure
me that the electronics are working properly.

thanks

Vacuum leak?

-----Original Message-----
From: quattro-bounces at audifans.com [mailto:quattro-bounces at audifans.com] On
Behalf Of Mark Rutherford
Sent: Sunday, April 18, 2010 9:37 PM
To: 'Quattro List'
Subject: 90 90 no fault codes.

I have a 1990 90 FWD 90 that has developed a random hesitation while
accelerating.  Went to pull the codes and get nothing, no 4444.



I inserted a fuse into the fuel pump relay, no light in the dash.

Replaced the bulb in the dash, inserted a fuse in the relay.  Check engine
light came on.  Waited over 5 seconds removed the fuse and the light went
out.  No codes, no 4444 nothing.

Went to the diagnostic connector.  Inserted the LED and the resistor,
grounded the ECU, LED came on.  Removed the ground, LED turned off and
nothing happened.

Tried the diagnostic connector again. Grounded the ECU, check engine light
comes on.  After ground is removed nothing.



Any Ideas?



Thanks

Mark Rutherford



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No virus found in this incoming message.
Checked by AVG - www.avg.com 
Version: 9.0.801 / Virus Database: 271.1.1/2819 - Release Date: 04/19/10
12:31:00