Hi all, I have some electrical issues that have gotten worse in the 11 months that I’ve owned this truck. I bought an extended warranty that should cover all of the issues, but my local Ford dealership wants to charge me $340-550 for diagnosis, but if you guys and girls could steer me in the right direction, I could figure it out myself. I do strongly believe I need a new PCM vs having bad wiring harness issues, but I’d like to know more instead of throwing money at parts. I sold my OBD2 scanner when I retired from wrenching in the late 90’s so I have nothing else besides my knowledge to work with, but this one has me stumped. Here is the list of issues;

*Window switch doesn’t auto up and when it does, it goes all the way up and immediately goes back down halfway, intermittently. Plus it also does it when I manually use the window button.
*Blinkers in side view mirrors stopped working.
*Side view mirrors heaters don’t work.
*Battery leaking.
*Radio shuts off when driving and sometimes comes back in by itself.
*Drivers seat stopped working.
*Rear park aid/beep works intermittently.
*Service fast track, antilock and slippery when wet lights turn on and go off within a few seconds.

I sincerely appreciate any help you can and will give to me.

Thank you,
Thomas

 

From your description , well,,,,,,,,may not be the PCM..

There could be an issue with the network communicating.and a capable scan too should reveal if there is a problem there.

If you decide to replace the PCM, it needs to be programed to your particular vehicle or the security system will not recognize the code and will not allow the engine to start.
Then,,,,,,,,,,,,,,,,,,,,if you decide to reinstall the original PCM ,the system becomes confused and will not work with the original PCM either and now will not start.

These things are important to know BEFORE attempting any changes. If you supply your VIN to the company selling the replacement PCM and they program it to
"As Built" specifications, then it should start and run. Hope we can prevent you from having problems.like having to tow the vehicle to a place that does programming or paying for road service from a place that can do it.

 

Thanks Hanky, I’ve never been a parts swapper, that’s why I’m trying to get some suggestions first. I read on another forum that there truck flashed thing on their dash too and it had to do with their rear camera wiring harness. Weird to say the least.

 

A little reminder, there is a network comprised of several modules in your vehicle that communicate with one another.

If one of these modules malfunctions or doesn't function at all, communications can be affected and problems show up.

Capable scan tools, specific info , and how the system works all get into the picture and diagnosis and repair can get a little complicated.

Sometimes we have to bite the bullet and have a good shop check things.
There is much more electronics in today's vehicles than the first space ship that went to the moon, think about that !

 

People talk like a good scan tool is expensive.

Download ForScan full version (free) to a laptop and get an OBDII to USB adapter for $60 or so.
Even the Lite version for a smartphone is very capable. Minimal download cost and adapters can be had for around $40-$50, with the most expensive one at $140 (but it is nice).

 

When you're tackling those electrical gremlins in your truck, first things first: dive into your ground connections and wiring harness. Get down and dirty looking for any signs of corrosion, loose connections, or wires that have seen better days. Think about it, have you given your engine a good wash lately? Sometimes, splashing water around can lead to sneaky moisture getting where it shouldn't, causing corrosion and electrical headaches. Bad grounds or some frayed wires? They're often the sneaky culprits behind those weird electrical issues.

Now, about that leaky battery situation – let's not overlook that. Kick things off by giving your battery and charging system a good once-over. Here's a nifty trick: disconnect the battery terminal, give it a moment, then hook it back up. It's like giving your truck's electrical system a mini reboot, which can sometimes kick those minor glitches to the curb. You gotta make sure that battery's in fighting shape and the alternator's doing its job. Remember, a lot of those electrical quirks can trace back to a wonky power supply.