Bad Power Control Module?? HELP!

It's been a while since I've been on here...
I have a 99 XJ with 4.0L and automatic.

I have a big problem. I suspect my Power Control Module(PCM) is dead.
Could any of you familiar with this lend a hand?

This morning I went out to turn my truck on and the engine would crank but it wouldn't start. So I figured either there is no spark or the fuel injectors/fuel pump aren't working. I also realized that the fuel pump didn't run for 3 seconds or so when I moved the key to the RUN position as it normally does.

I also verified there is no spark.

The gauges on my instrument paned did not move one bit but some of the lights did work as well as the odometer.

After a couple seconds in the RUN position, the odometer read: "no bus" and the check engine light turned on.

I luckily have the service manual. After doing some reading I realized that this meant the dashboard electronics isn't receiving the CCD(Chrysler Collision Detection) data info that appears to be generated by the PCM.

The PCM is also supposed to energize the fuel pump relay.

I did the dashboard self test by pressing down on the odometer reset button and turning on the ignition and all the gauges and lights worked fine so my conclusion is that the dashboard is getting power, but isn't getting the data to move the gauges.

I checked all the fuses in the Power Distribution Center and they are all OK.

I disconnected and reconnected the 3 PCM module connectors and still nothing. I checked the A22 pin and which is supposed to be the battery voltage input from the battery and it is getting battery voltage.

Unfortunately I don't have a DRB scanner tool but just might go get me the Auto X-ray tool that I've had my eyes on for a while.

Can anyone offer some suggestions?

I read that when a new PCM is installed, you need to set the VIN code and current mileage which makes me think this might only be able to be done at the dealer. I would like to avoid that expense if possible.
Anyone know how much a PCM is?

I'll be awaiting suggestions.
I'm going to check some ground connections that exit the wire harness near the PCM. Maybe it's something as simple as a bad ground.... but the case of the PCM is all metal and bolted to the fender so that suggests the ground isn't to problem.

Thanks for you help. Please respons ASAP. This is my only vehicle and I need to get to work on Monday.

MAP

does the check engine light up with the key on? if not, unplug the crank sensor and then see if it does. sometimes one of the sensors that use the 5 volt supply circuit can short out and shutthe pcm down, usually the crank sensor. try to unplug them one at a time and see if you get the check engine light if you do the last one unplugged is the problem. if not you probably have a bad pcm. very few pcms fail usually from being jump sterted with jumper cables reversed.

this may sound stupid, but unplug the airbag control module, that may have shorted on the bus wires and that can shut the system down. i have seen that one time before, the airbag modole is under the console between the front seats.

Nail on the head, you got it, this guy knows his stuff

You were right on. I disconnected the CPS and turned the ignition to the RUN position. The gauges all worked, I could hear the fuel pump run and the check engine light turned on.

The CPS must have been shorted like you said. I didn't think the PCM was smart enough to have short circuit protection but it must.

I don't usually see questions this technical come out on here but I'm glad there's someone here who can provide the helpful info.

I tried connecting the sensor again and got the same symptoms.

Thanks again. Now just the fun part of buying and installing the thing. It doesn't look easy.

Thanks again.

People.... You have a fuel injection, PCM, or electrical question... contact jneary. He's the man.

Manuel

thanks, i'm humbled. actually being a jeep tech for the last 17 years, i have seen my share, especially since i do the majority of the driveabilty work. just remember if and when you go to the "stealership" as it is called, you're getting your moneys worth, the extra expenses we charge helps pay for factory training also.glad to be of assistance!