F150Torqued

This should help match up the pins to the wiring diagram.
https://www.f150forum.com/attachment...nce_values.pdf


The reference or NORMAL expected readings on various circuits / things are helpful


Keep us posted. Give another read to @redfishtd's comments.

adanvjr

Thanks Torqued.

Redfish,
Thanks for the encouragement and I agree.
I'd rather be paying a few hundred on parts, than several hundred each month on another truck. My plan is to get out of debt, not get deeper in it.

I guess my frustrations got the best of me yesterday.

I'll be updating as I continue to troubleshoot it.

adanvjr

Okay.
I did some further checking for continuity. Had a coworker help.

I first checked the harness plug that goes into the sensor to see if there's an open/short. Placed 1 probe into the pin inside the harness while I used the other probe to pierce into the Orange wire (which feeds to the PCM). It was good, no opens.
Did the same or the grey/red wire, it was good too.

I had a coworker hold one probe into the pin on the sensor harness plug. I used the other probe to check on the harness plug that connects to the PCM (Engine Harness Pin# 44).
No continuity.

However, the probe looks too big to fit into the pin was preventing it from making contact.

How easy it is to open up the actual harness plug on the PCM?
It looks to have only 2 plastic latch clips.

I didn't go further as I was worried I could break it.

F150Torqued

I would be in favor of first just sticking a needle or straight pin or small gauge piece of copper wire into the female PCM plug before taking it apart.

adanvjr

Okay, thanks.

adanvjr

I went again with the continuity test.
I used a small metal paper clip to insert into the pin holes for the multimeter probes. Continuity check passed.



I forgot to advise yesterday:
The Harness Plugs for BODY and ENGINE listed on the Pinout Diagram are different:

Looking directly at the PCM from left to right:

The diagram shows the plugs being from left to right: BODY - ENGINE - TRANSMISSION

My truck has them from left to right: ENGINE - BODY - TRANSMISSION

F150Torqued

HOLLY SMOKE!
I've used the Diagnostic Ref chart many times to check OBDII readings against my Torque Pro app, but not physically to test voltages / wire pin-outs. Darned lucky the harness on mine is formed well enough I always just plugged them back where they WERE. Looks like Body & Engine are same number of pins and could be swapped !!!!


Thanks for the heads up! (guess the technical writer decided to 'alphabetize them') LOL

adanvjr

Yes. When I changed the PCM, I marked each plug to ensure they go back in the right spot. Thank God I did, otherwise I probably would've ended up shorting out the rebuilt PCM.

I opened the BODY harness plug and was wondering for 15 minutes:
"Where the heck is the Orange wire that feeds to the CMP Sensor?"

I plug it back in, pull the other one out to open up, and the correct wires were right there.

e2dx

Just curious, any further updates on the issue?

adanvjr

In short, no. Still have the same codes but no issues.

I had a friend come by and advise that a TSB was sent out about the alternators and the same exact codes I was getting (P0345 & P0349, but no drivability issues)

apparently, the generator would give AC noise and would interfere with the sensor and confuse the PCM.

If you unplug the alternator and crank on the engine, the code would immediately go away. When you plug it back, the same codes will come back. If this happens, then the alternator needs to be replaced.

Friend said those alternator testers at Autozone and oreilly don't really check for AC noise on the generator. Which is why it passed at oreilly.


I did the unplugging test at home, but it couldn't be resolved.

Since then, I've pulled dozens of trailers, did +70 mph on the highways, without any issues

After much debating, I've decided to let it be and drive it as is. I've spoken to others and they all informed that unless there's the ticking/knocking noise, don't bother the timing components. Plus, even if I rebuilt the timing set, it's going to have to be rebuilt again in less than 100k miles. Which is why the 5.4L was scrapped.