Faulty ECU - Knock Sensor 1 signal

[DeS]

Hello,

I have a problem with received (bought) 3B stock Ecu. Engine starts, car runs, but after hiting boost it gets cut-off. ECU memory give Knock sensor 1 - NO SIGNAL fault. Wiring is checked and OK, both sensors are OK.

Someone told that old (from Audi 200 20V) 3B ECU sometimes have electric problems with internal wiring and NO SIGNAL fault is as result. Does anyone had same or maybe any solution how repair the ECU.

Cheers!

[UrS4boy]

G61 and G66 Knock Sensor info

Can't help with the 3B issue but I can provide you more G61 and G66 knock sensor info. Click on the link below and then on the Knock Sensor label on the right side of the diagram (the other labels are live as well)

http://members.shaw.ca/speedtek/UrS%20Engine%20Bay%20Device%20Map.html

[prj]

3B loom has resistors in it for the knock sensors.

With a second 3B ECU, the fault is not there? Only with this one?

[DeS]

3B loom has resistors in it for the knock sensors.

With a second 3B ECU, the fault is not there? Only with this one?

Yes, on previous ECU (modified) was everythig OK. When I change sensor plugs to check the sensor, fault is still on first one KS.

[prj]

The knock system is not in a proprietary chip on these ECU's.
If the 2nd one still works, just trace Pin 11. it will go into a capacitor, after that through a resistor, and into a chip, which is a solid state relay.
In your case, what can be shot are a few caps, a resistor, the relay or the control to the relay.
In all cases, it is repairable.

I don't know all the exact numbers for the 3B, only for ABY/AAN/ADU ECU's, but the system is identical on both.

I would say the best idea would be to set up the ECU on the bench, and then pulse Pin 11, and see how far the signal goes.