PCM is located here:
Attachment 277411
courtesy of Subford

The connector has a single large bolt that holds the connector to to the computer (PCM). Yours is a little larger than the one in the photo. Disconnect the battery before removing the connector, reattach when completed then crank the truck to check for spark.

 

thanks. PCM unplugged, still only way to get spark is to hit the coil negative with a negative jumper wire - not firing through the circuit.

and I still can't shut the alarm up. my neighbors are going to kill me.

 

Pull the power wire off the horn, that will at least deal with the noise. if it is aftermarket there is a speaker somewhere the wire should be able to be removed from

 

thanks. i do pull the wire after a second or two each time I set off the alarm. but afraid when it's alarming and I don't hear it, that the alarm will be interrupting the circuits, in addition to the undiscovered problem. so always hooking it back up. I thought it was a factory alarm, but when I pulled the PCM, and it still was going off, got me thinking it's aftermarket. In which case maybe it can be removed? On the list of things I worry about, someone stealing this truck because it doesn't have an alarm is at the bottom, or lower. can probably ditch the wheel locks too, dont think anyone it going to be running off with my rims and tires.

 

Looks like you are going to have start tracing ignition circuit wiring. That alarm needs some way to prevent the engine from running when it is triggered. Looks to me like it kills the ignition.

 

The security system will be a separate module from the PCM whether it is aftermarket or Ford, or even aftermarket Ford.

 

I see. I think it's OEM, and I believe if it is, it can't be removed/permanently bypassed?

But I apologize for misdirecting the thread into an alarm discussion. The ignition problem which killed my truck on tuesday has nothing to do with the alarm. Two days later I flipped a switch at the drivers seat, so now the alarm is armed, and apparently since the car won't start I can't get it back to where it was - even though I've thrown the same toggle a dozen more times since. It's annoying the crap out of me, to the point I'm ready to give up. But it's not what caused the spark to die, it is a newer problem.

does anything elaborate need to be done in order to get the ICM properly grounded? I just bolted it to the heat sink, and called it installed. Think I remember reading something about dielectric grease needed, but now can't find that thread.

 

Check? or replace the fuel pump relay. Had a buddy who's 88 Bronco 5.0 died suddenly with a low amount of fuel in the tank and would not restart. After cooling off for several hours and some fresh gas it started and ran for about 1/4 mile before it died again. Fuel pump relay was the cure.

 

You need the heat sink--> thermal paste to put on, not dielectric grease, Artic Sliver, or Super Lube, are 2 good versions.

 

still haven't figured this thing out. I did track down the alarm, it was an aftermarket 'viper' -- it's out now, that might be more of a relief than fixing the truck will be.

Here is where I am today, almost two weeks later. Positive at the coil is good. Negative at the coil does not pulse. If I manually touch and remove a negative jumper to the coil negative side, I do get a spark in the tester. So I believe my coil ( which is new) is good, and my positive circuit to the coil ( ignition swtich, fuses, relay, left behind alarm wiring, etc.) is good.

The number 6 on the ignition module ( module is also new ) does pulse a positive. Which leads me to conclude the distributor ( also new) is working correctly.

The number 2 on the ignition module, which if I'm understanding is supposed to pulse negative -- that isn't working. With the key off, it does have a good ground, but once the ignition is on, or cranking, there is not enough to light up a test light on this wire.

I've been through the haynes manual, the easydiagnositc web page -- still can't figure this out. Everything points to a bad ignition module, I think. But my module is brand new. And I plugged up the old one again, no difference. I guess there is a chance my new one was a dud, but seems more likely I'm the problem, not the new module. I was hoping the autozone could test the module, but no luck.

Don't even want to mention how much I've spent on a rental car since my truck dies. but have to admint, loving the 2021 air conditioning in this weather!

At the module, if the pip ( #6) is pulsing, and the postive(3) and negative (1) are good, and the SPOUT connector is removed -- it HAS to be a bad module if 2 isn't pulsing negative, right?

 

In case anyone was wondering, or stumbles onto this thread with a similar problem. It WAS the ignition control module that was preventing the motor from starting. Bought another new one from autozone Plugged it in, truck started right up.

But it's not running right, and now throwing a P1351 Ignition Diagnostic Monitor Input circuit code. Any ideas? thanks.

 

Thanks for the reply back and yet another example of aftermarket ICMs are very prone to failure and/or DOAs. Glad you are back on the road!

 

not quite back on the road. While it does start now, and sounds ok idling - and the anti-theft alarm is out - which is a nice start --- running very rough when I test drive, and throwing a lot of error codes; Ignition Diagnostic Monitor Input circuit , Bank 1 too lean, Bank 2 too lean.

perhaps the timing is off, although i was sure I hit the new distributor exactly where the old one came out. Trying to check with a timing light, but the balancer is pretty rusty, so not sure on the timing marks. There is a groove in the balancer, I was assuming that is TDC, so I put a little white paint there, but that one never seems to come up, no matter how far I advance or retard my light. Looks like a previous owner put a red dot on the balancer, but don't know if that's supposed to be tdc, or where he timed the motor.

would the timing being way off throw all of these codes? or maybe I got an icm that was a little better than the last one, but not good enough? I am really at wits end with this truck, have spent a lot of time on line shopping. I guess at least now that it's somewhat running I can take it over to a shop without being towed. But would have liked to finish this up on my own.

 

You do have the timing light on the front spark plug wire on the passenger side? Just checking.

 

What color is the new replacement ICM? It should be a black colored version for the CCD ignition your truck uses. Many parts books are wrong including Ford so you may have been sold a gray colored Push-Start ICM. That will trigger the missing IDM signal error code. The engine will start and run but performance and MPG may be affected when using the wrong ICM.