Hey guys I am new here ive been on other forums but I come to you today with a problem that is bugging me and I wanna prevent it from getting worse.

So my Z28 threw a 332 code which means Knock sensor, so I check the sensor and its fine, so is the connector... I did a voltage test from the connector to about 8 inches up (as far as I can go) and there is no voltage...

Now I know the ECM/PCM is on the pass side under the hood near the firewall, I was wondering if anyone has a schematic or diagram on the wiring I know its a DK BLUE 496 going to D22 KS signal. Im guessing the wire came off the ECM (well its wishful thinking because a little solder and its good to go) if the wire is ok after I trace it then its a bad ECM which sucks because I cant buy one tonight.

What is the proper way of doing this?

If anyone can help it would be greatly appreciated. Thanks guys

 

A schematic is not going to help. You already have all the information it would give you and know where it goes. You are doing the right steps. Just trace it all the way back to the PCM and see if there is voltage leaving it. Make sure you are measuring it right and remember that the voltage will be lower if it is a complete circuit to the KS. With the KS unplugged, you should get near 5v dc.

 

I tested the wire voltage with the ks off and on and I got nothing, im sure the wire is off the pcm... which hopefully I can just re-solder.. but do I just take the pcm off and check or is there something I should before hand?

 

You're at least going to have to pull the PCM out to get to the wires. Leave it connected and see if you can back probe the wire for testing. It may even be just a backed out pin on the connector.

 

the connector on the actual KS? cuz i checked everything up til I couldnt test the wire anymore which is about 8-10 from the connector, the connector and the sensor and everything is good...

Unless youre talking about on the PCM itself

 

I am talking about the PCM. That is where the voltage comes from.

 

alright I got the PCM out... now it has a bunch of star bolts on it, I dont even think I have star keys that size which sucks... but now what? do I open it up and take a look inside?

 

Or do I open up the small door on the PCM itself

 

You need to test at the wiring connections. You don't need to open the case.

 

i think he means the pin coming out of the connector, the pins can back out of the wiring connector , the plastic peice that plugs into the pcm.
sometimes when you plug in the connectors it will actually push the pin out of the back of the connector instead of sliding onto the pin on the pcm.

 

Look at Shoebox's PCM pinout diagrams. That will show you the correct connector (D = Blue connector). It also tells you how the pins in the connector are numbered, since there is more than one dark blue wire in that connector.

How did you test the sensor to determine that is was "fine"? What was the resistance, with the harness connector removed, measured from the single pin on the sensor to the block as a ground? When you checked the voltage on the wire, was the connector off the sensor, the key turned to on, and the voltage measured from the connector pin (and then further up the wire) to the block as a ground?