97grand4.0

That does sound more like the crank position sensor. Can't say for sure but, ..the auto shut down relay controls voltage to the coil, and this asd relay is controlled by the pcm. Without a signal from the crank sensor, it will turn the coil off.
So, you need to verify 12v at the coil, while cranking.
If none I would think crank sensor. HOWEVER, I must add from personal experience that the cam sensor, or distributor switchplate, (proper name) that thing you called the pickup coil, yes that little plastic wafer thing, can produce the exact same problem, and it rarely throws a code, where the crank sensor usually sets the code. I replaced my distributor once and the one that came inside the brand new distributor worked fine for about 5 days then wouldn't start. Put in a junkyard 100k mile Mopar switchplate, and it's there to this day.

Mick96XJ

Ok I'll test the voltage while cranking and if there is voltage or isn't what's the next step?

Mick96XJ

I also did test the resistance on the crank sensor and it tests good but when I switch the leads around on the tester it shows resistance, I thought it didn't matter which ever way you hook the leads up?

97grand4.0

Verify 12v at coil while cranking. Without snagging your clothing in the fan.

Mick96XJ

ok so there is no voltage at the coil while cranking but I can get spark if I jump the asd relay. The connector off of the main harness for the crankshaft position sensor has 5.15 volts on 2 pins and .444 on the last that doesn't seem right they shouldn't all have voltage?

97grand4.0

No. Don’t jump the asd relay either, What this says is the pcm is not getting either the crank or cam sensor signals. After re reading your posts I am still unclear, did you replace the cam and crank sensors, and did you use Mopar sensors. Because that is what the next step is imo
At this point, if you haven't ever replaced the Crank Position Sensor with a Mopar, you are long overdue, and it makes sense to put one in. Then turn the key and start it up. And you could try a different cam sensor or 'distributor switchplate' as I alluded to in previous post. Diagnosing the cks and cam sensor is difficult because the pcm was not so good about setting the code for these years. Sometimes did sometimes not.

And have patients, my Dr. said patients are a virtue. If this was easy, everyone would be driving 24 year old cars and the dealers wouldn't be selling new $50000 trucks.

Mick96XJ

Ya I replaced both sensors I got them from orileys, I would rather not spend another 150 bucks on sensors so I'll just grab them from the junkyard this time. Would you happen to know what the voltage is supposed to be at the cps plug with the ignition on?

Mick96XJ

And also where do the 3 wires come from for the cps? I cant find any wiring diagrams anywhere!

97grand4.0

There are diagrams all over the net, and on this forum.
I would start with the one under the cap.

Mick96XJ

It ended up being another bad pcm, my original one was bad and orileys sold me another bad one, it was sending 4 volts down all the grounds for most of my sensors. I ended up getting a free one from a friend out of a 99 xj, plugged it in and it fired right up thanks for the help guys👍

97grand4.0

Thanks for letting us guys know how you made out.
Interesting, so you say a 99 pcm worked in a 96. I guess possible, but wouldn't work the other way around because of the skim and vin and mileage requirements of the 99.
Interesting you can "send 4 volts down all the grounds" since they are grounded to 0 volts, how did you measure that? You mean maybe that when you unplug the sensors you saw 4 volts on the signal line?
Your original post said that you checked, but not replaced,, the 'ecm'
Good luck with your 99 SJ.