96 XJ - engine died on highway, cranks, doesn't turn over.

[fsupaintball]

96 XJ

I was on the highway at normal operating temp, hit the button to turn off cruise control (coincidence maybe), and my engine died. Electronics all stayed on. Pulled over and tried to start up. The starter cranks good and hard, but the engine never turns over.

I messed with my shifter (neutral safety switch), re-plugged the CPS harness, tried swapping the fuel pump relay, no difference made. Towed to a Big O near work to see what they saw.

Errors pulled: P1389, P1388.
"Auto Shutdown Relay shut and open; no auto shutdown relay voltage output at PCM"

They also say 12V should be coming from the PCM, and they're only seeing .3 volts. They tried swapping in another Crank Position Sensor and it made no difference.


Anyway, they sounded a little unsure but said the next step is a $500 PCM replacement. I'm trying to figure out what to do next. Suggestions?


Other notes:
-I'm fighting an overheating problem with this Jeep, but it was running at a normal temp at the time.
-About 2 weeks ago I swapped BOTH manifolds, and put in a 97+ style intake manifold and swapped around some vaccum hoses to make it all fit. The hoses look OK.
-Neutral safety switch was replaced a few months ago.