Pulling 3B, AAN and ABY Fault Codes with no CEL

[UrS4boy]

888

[cooperquattro]

good idea but vag com is easier

[prj]

Most cars don't have that third terminal!
In fact, the only ones I saw with that blue terminal were cars with the 3B engine...

My car, as other AAN engined cars in this part of the world have a black and a white plug only.

[cooperquattro]

i thought blue one was for abs??

[UrS4boy]

Most cars don't have that third terminal! In fact, the only ones I saw with that blue terminal were cars with the 3B engine...My car, as other AAN engined cars in this part of the world have a black and a white plug only.

Okay. The first diagram was from a VAG AAN self study document. The second was from a 3B self study document. I know that the North American UrS4 and UrS6 only got the white and the black terminals (see photo of my car below) but we also got the CEL. If you guys didn't get the CEL or the blue terminal, then I guess you are screwed.

I tried. Or at least I tried to try. VAG 1551 (or VAG-com) it is then.

[merlin's S4]

This may not be the case for all but certainly is true for many:

There is a small bulb holder hidden in the wiring behind the instrument cluster which is for the MIL lamp. Remove the instrument cluster, find the bulb holder, fit a bulb and then fit it into one of the empty slots on the instrument cluster (I used ASR) and voila, one diagnostic light!!

This light will come on with the ignition and then go out with the engine running. If the ecu senses a problem whilst driving it will illuminate and it can be used to blink out the fault codes by shorting the black and white diagnostic terminals under the bonnet.

[UrS4boy]

Thanks. Exactly as I had hoped. Confirms my thoughts that the blink code capability had to be there *somewhere*, even if it was not fully enabled from the factory.

[Zoig]

As I wrote onto the Other topic, my car had the blue connector missing from the ECU connector (don't remember terminal number right now, in the middle row somewhere). Adding it enabled me to create CEL light.

[fish]

what colour is the "tape" on the MIL light? As someone has pulled my airbag light i have two wires IIRC one had yellow tape and one a maroon red. Oh, and what does MIL stand for?

Cheers.

[prj]

fish, connect with vag-com to the airbag controller, the airbag light will light IIRC.

[UrS4boy]

... Oh, and what does MIL stand for? Cheers.

Malfunction Indicator Light (MIL)

[UrS4boy]

what colour is the "tape" on the MIL light? ..... Oh, and what does MIL stand for? Cheers.

The wiring to the Malfunction Indicator Lamp (MIL) is either White with a black stripe or White with a blue stripe from Pin 22 on the 55 pin ECU to the Data Link Connector and the MIL lamp holder (socket) and then Black with a Blue stripe leaving the socket (and going I am not sure where).

[S2central.net]

According to AAN schematics I have - all of them have the wire in place for CEL/MIL bulb. Its a blue/white wire on the ECU side that as shown to come directly from engine loom into cluster where it connects to the bulb 'K66'. The other side of the bulb is switched 12V on black/blue wire.

If its not obvious - when the ECU wants to light the lamp - it pulls ECU pin 22 to 0V so that there is a current path thru the K66 bulb. Easy peasy.

[S2central.net]

more correctly - the black/blue feed wire comes from same intermediate terminal as the reverse light switch on AAN - hence my confidence that *all* AAN should have it in place - though someone will likely prove me wrong... I am just saying what the wiring diagram shows.

[UrS4boy]

more correctly - the black/blue feed wire comes from same intermediate terminal as the reverse light switch on AAN - hence my confidence that *all* AAN should have it in place - though someone will likely prove me wrong... I am just saying what the wiring diagram shows.

LOL. When I said above that I didn't know where the Black/blue wire went, I actually did. Except the diagrams show going through the reverse light switch, which seemed *very* strange to me. I guess the power to that switch is hot all the time, not just with the key on (??).