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good thought...... and apologize as did not even consider speed/crank sensor..... OK..looked over Bentley last night and about 1/2 dozen "knock sensor" dialoques. Feel confident that the sensor(s) get a reference voltage from the ECM , believe due to the fact that swapping bonnets to sensors, both sensors are good. As your post #18 confirms all pin outs #108 -ground?, #106-G61, #107-G66,#99-+ref. voltage all have good (proven with test light) continuity. One other thing to consider is that the ECM does not always recognize "inputs" until other functions are complete, i.e.,the CCT cam advance/retard inputs are not recognized , or do not show a fault (if bad) until SAIP pump has completed it's "warm up" cycle......in other words maybe ECM does not recognize signal until other conditions are met (maybe engine temp.) but then it seems that it would have a separate reference voltage input to the G61.......…..sorta of leaning ,with regret, to input circuit in the ECM's surface mount chip for G61
 

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Discussion Starter #62
Well I know the drive cycle doesn’t test the knock sensors until operating temp has been reached and above driving speeds of about 40 mph.

If it does help to fix the knock sensor issue... my SAIP isn’t working. The pump itself works since I removed it and bench tested. There is something wrong with the wiring or fuse/relay.

Is there a way to see these other inputs on vag to verify if they are working? Like block 26 is for knock sensor voltage.
 

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was using SAIP as an example ... sometimes ,like the engine has to warm up before all faults/sensors are checked ,check the SAIP fuse inside ECM cover/box ,easy to remove cover the only screw that presents any problem is the back one , you have to take out little plastic plug in wiper valence cover to get to it, might even have to turn wipers on ,stopping in vertical position ,40 amps . As example I know that the camshaft sensor might be sending signals that the cam timing is off but the ECM does not acknowledge that fact until SAIP pump turns off ,but it is still getting cam signals , G61 in your case is not even reporting for active duty. the two feed wires for G61 and G66 are different colors thus spliced ,that is all I can now think of even though you have extensively checked it like 3 ways from Sunday
 

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Discussion Starter #65
Oh yeah I’ve already got the cowl and wipers removed for easy access to ECU.

So since we’ve checked everything we are considering the ECU failed?

I guess the next step would be to research how to swap ECU.

I know I’ve got immobilizer 3. I just don’t know the steps to swapping.
 

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seems like the only avenue this far down the road, ironically took my wifes Kia Soul to get oil changed and noticed CEL on ,ran scan and bank 1 knock sensor "out of range"...... neat
 

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Discussion Starter #67
? well out of range may be easier to fix than low voltage.

Been doing a lot of research into getting ECU replaced. Will hopefully be getting it done soon.
 

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wish I would have been of more help, had a "silver bullet" , if it is the ECM it will be I believe a first I have seen on this forum in regards to knock sensor.......keep us in the loop as I am still interested
 
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