Need PCM pinout for 01 grand prix 3.1

[Convert92]

Hey guys, new to the forum and want to get to know everyone. I have an 04 grand prix gtp, but am working on a friends 01 with the 3.1. Knock sensor code p0327, sensor is good with 100k ohms resistance to the block, wire has 3 ohms of total resistance from pcm to knock sensor with no short to ground, and last but not least at the pcm connector with the terminal removed there is .05v. Replaced the pcm since all powers and grounds I found on the pcm connectors were good. Still throwing the code after driving 50ft. I think I am missing some small detail and it is kicking my a$$. Please help me... Thanks, Convert92.

[Convert92]

Well, I used a thread I found about wiring diagrams and found the correct one for the pcm. I have all the correct wiring, powers, and grounds to the pcm and still not getting the correct 5 volt reference out of the pcm for the knock sensor. Any thoughts, really, any at all. Oh and ohmed the wire from the pcm to the knock sensor and it was actually 1.5ohms. I double checked on my trucks knock sensor and has the correct 5 volt reference to the knock sensor, I just don't know. Probably a bad reman pcm I'm guessing.

[AJ1G]

Did you see the correct 5V reference at the PCM end of the circuit?

With or without the lead to the sensor disconnected either at or as close as possible that you can measure from the PCM on the lead to the sensor?
If you see the 5V at the PCM with the lead to the sensor disconnected, and it drops when you have the sennor lead connected to the PCM, I would suspect a possible abnormal current leakage path to ground on the lead to the sensor that is dragging down the voltage .

I had a similar problem a while back where I was throwing several codes, and the gas gauge was intermittently not working. Turned out to be a partially grounded PCM 5V reference circuit that fed several things (TPS voltage excitation, gas gauge voltage excitation, forget what else..). Root cause was chafed insulation on the 5V reference wire to the TPS, the wire bundle to the TPS got pinched into the throttle body inlet/MAF boot joint when I was putting the boot back on after an air filter replacement.

Always check the wires before changing modules!

Chris B. Electrical Engineer
Stonington, CT
2001 Bog Stock GP SE 95K

[AJ1G]

Should have mentioned in response to your original question re PCM pin out - When I was chasing grounds on the 5V reference circuit for the TPS and the gas gauge, I had very good luck using the schematics available for free on the AutoZone web site. They maintain a huge searchable database of technical documentation searchable by vehicle/model year. You have to register on the site to access the stuff, but there is no charge to register. Once you register you can set up your default vehicle(s) that you will be looking up info for.

[Convert92]

I had checked the autozone wiring diagrams and found to be for the wrong setup, had me chasing for incorrect power and ground locations. Thanks. I am going to check the rest of the 5v references. It is just awkward that only the knock sensor circuit is affected, no other codes, complaints or issues.