yours does have a 12v ref, I was assuming it was a 5v without knowing what vehicle. The sensor won't put out a signal unless its cranking

 

I just check for resistance in all three wires to the crank sensor an all test ok. I did that because the signal wire is showing a ground when tested with my power probe. I'm not good with electrical but that tells me there is a short to ground on the signal wire. An I on the right path? I have the battery charging now to get a good reading on the signal wire while cranking. Once I do that I'll let you know the outcome. But does it sound like a short to ground in my computer if all the wires test good when the signal wire shows a ground signal?

 

Just did a crank test with good battery and now I'm getting nothing for a signal. Correct me if I'm wrong but I think I have a short to ground in the pcm. What do you think? And the crank sensor is brand new I've already returned it once since I replaced the original one that was in it when it ran.

 

so you said you checked the wiring to the ecm and to the crank sensor plug ,correct.what kind of readings did you get on each wire.maybe your ignition module is bad.best way to check all the related circuits in the ignition system is with a lab scope.

 

I checked for resistance in all three wires from the crank sensor plug to ecm. All tested fine no resistance. I don't have access to a lab scope or tech two scanner. The only thing that I see wrong with the sensor is it is putting out a signal. And it's the second replacement sensor since it ran. Its Gettin good power and ground but the signal wire is showing ground when I hook up my power probe to it.

 

the power probe showing green (ground) basically just means the wire has continuity and is grounding through the other end which doesn't necessarily mean theres a short but its possible. You say the crank sensor isn't putting out signal where are you testing for it? If the crank sensor is unplugged there will be no signal you'll have to backprobe at one of the connectors. If all the wires have good continuity readings then basic theory would say its the sensor itself, the reluctor or ecm.

 

The sensor is plugged in I'm testing for signal at the middle wire I think it's white with a black stripe. I know the reluctor isn't broken I just did the oil pan gasket and had the harmonic balancer an all that off. I've replaced the sensor twice. But I wouldn't rule it out cuz you never know. Can I test the sensor for continuity out of the vehicle to see if it's bad?

 

Can the reluctor go bad without one of the tabs breaking off? If I remember correctly it was a ring behind the harmonic balancer with 3 or 4 big tabs on it. Like a speed sensor ring but bigger tabs.

 

if its not physically damaged or out of place the reluctor should be fine, only other thing would be the air gap of the sensor, where did you get the replacement sensors?

 

Autozone but it worked fine before I replace the wire for the passlock sensor that was corroded. Got spark back an everything. But the engine got flooded cuz I didn't unplug the injectors. An a few weeks ago I was getting .2-.3 volts for a signal now I'm getting nothing. And I'm pretty sure the sensor is in all the way.