no voltage from knock sensor harness
08-17-2011, 09:25 PM
#2
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Update. After finding no voltage going into the knock sensor harness I tapped into a 5 volt source. However the codes still come up for low input. Then today I installed a new knock sensor harness, the one under the intake. Checked the voltage and then went for a drive. Sure enough the codes came up again. I need a wiring diagram for a ls1. All the schematics I get here and online don't show me where all the wiring goes to and comes from. I know there are two knock sensors two signal wires. Also one power wire and one single wire coming from the pcm. Where does the second signal wire go to? I am all confused.
08-18-2011, 11:11 AM
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What I want to know is where does the knock sensors get there power from? The plug going from the pcm there is a blue wire, signal wire and 1 grey wire, power source. On the pcm side there are just the 2 blue signal wires. Where do these all tap into?
08-22-2011, 05:44 AM
#6
They are 1 wire resonant sensors.
"power" comes from the PCM through those wires.
Engine Knock Sensors, Part 1
Engine Knock Sensors, Part 2
"power" comes from the PCM through those wires.
Engine Knock Sensors, Part 1
Engine Knock Sensors, Part 2
