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Negative voltage at knock sensor wtf, is this correct?

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Old 07-25-2012 | 12:08 AM
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Default Negative voltage at knock sensor wtf, is this correct?

I went by Shbox's test procedure for testing the knock sensor at the pcm and at the harness of the KS.. PIN 22 D on the PCM read correctly at around 5v. I then tested at the knock sensor harness and it showed -5v... as in negative 5v and not 5v like the PCM showed.

This was all done by the book step by step, had the key turned on and the knock sensor unplugged.

Is this wrong and wtf how do I fix this...


PS - this is all being done because of my weird "knock sensor bank 2 circuit 2 low input" code I've been getting with my scanner.. won't set the SES light and won't show up as a primary code in the scanner, it only shows up when you dig into "enhanced DTC's". My car has been hesitating bad lately especially at low RPMS and forget about going WOT, it breaks up and pops and this seems to be the reason why if it's ******* my timing up.
Old 07-25-2012 | 05:19 PM
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you didnt reverse your leads by chance for your multimeter and check witht he negative lead on the knock sensor wire? that will give you your negative reading.

one way to check if your knock sensor is working, is put your voltmeter on ac voltage, and literally knock on the engine with a ratchet, and watch your readings. knock sensors produce ac voltage.



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