Thanks, I replaced the CKP with another new one 2 days ago..... Does the duty cycle function use ac volts and hz on the meter?
I've never done a duty cycle test before....

 

Fluke 115 True RMS Digital Multimeter

This is my multimeter.

 

It has to specify "Duty Cycle", AC volts and Hertz are different. That's a nice DVOM, and it's designed more for an electrician. Duty cycle is something common in automotive.

 

I forgot to mention that the "business end" of the CKP has no marks on it at all.

 

I just thought of something....

My mom has a 96 Bravada that is exactly the same as this one. I should take those 2 PCMs and see if they work.

 

One more thing to check. This needs to be followed closely for the results to be accurate.
Unplug the CKP sensor.
DVOM on 20V DC scale. (nevermind, DVOM is auto range)
Volt meter positive probe to the pink wire in the CKP connector.
Volt meter negative probe to a good vehicle ground, to the battery would be great.
Have an assistant crank the engine over using the ignition switch.
Post the answer I'm looking for

 

9.5-9.2 volts on the pink wire on the CKP connector with the connector unplugged and the negative going to the battery while cranking the engine.

11.2 volts with just the key on.

Gotta love the 30' retractable test leads!

 

Damn, not the answer I was looking for. 1997 is well known for faulty ignition switches. They can cause all kinds of screwy stuff when the fail, or begin to fail. That test was checking the START circuit in the ignition switch. Start & run positions are different in the ignition switch. It was supposed to show battery voltage, which it did, meaning it's not the ignition switch. Gotta ponder a bit... ya got my curiosity going now.

 

You and me both Captain. I'm gonna try the 2 PCMs in moms Bravada tommorow to see if it will run with either one. It's trying my capabilities for sure. I've done timing sets, head gaskets, transmissions, transfer cases and a couple of heater cores in a bunch of these things, but this is a first for me on this problem. Lol

 

Back in post #6, you tested the yellow signal wire from the CKP to the PCM. The results came back good. What was NOT checked, (my fault) was checking the resistance from the yellow wire AND the purple wire to ground. If the purple wire is grounded out, the sensor will still be energized, but it might not work properly. If the yellow wire is grounded out, (pinched somewhere) the resistance to the PCM would be OK, but the signal will not reach the PCM.

Ignition OFF.
Unplug the blue connector at the PCM.
Unplug the CKP electrical connector.
Check resistance on the yellow wire from the CKP connector to the negative battery terminal. Must indicate open circuit. (OL on your Fluke)
Check resistance on the purple wire from the CKP connector to the negative battery terminal. Must indicate open circuit. (OL on your Fluke)
As a double check, measure resistance between the yellow & purple wires at the CKP connector. Must indicate open circuit. (OL on your Fluke)
Wouldn't hurt to measure resistance on the purple wire from the CKP connector to the PCM connector either. Must be less than 5 ohms.