I'm having an issue starting a 2017 f150.

Brand new 12v battery and key fob battery.
Lights in car work, radio works, and maybe half of the controls in the cabin works.
Checked every single fuse in the battery junction box and at the BCM, all good. All the fuses in the BCM have voltage coming coming into them.
When I connect the 12v battery, radio turns on, interior accent lights turn on and the instrument panel lights up. I click the push button start and nothing changes except I hear a couple clicks under the hood.

I connected an OBD2 scanner and it can many most modules but not the BCM, the PCM, or the APIM. Says "no communication" codes U0100 U0140 U0253.

What would be my next step, how do I check that either the BCM or PCM are bad? Did I miss checking some kind of high current fuse? Could this be triggered by some kind of anti-theft system?

If someone has any insight, I would greatly appreciate it!

Also, is there any kind of service where I can pay to talk to some qualified technician who can run me through diagnostic steps?

​​​​​Thanks!!!!!!!!

 

All three of these modules communicate over the HS1-CAN bus. HS1-CAN bus passes through connector C210. There are three connectors all the same except for the colours just to the left of the BCM and under the access door to the cabin air filter. C210 is the gray coloured connector on the left. I would pull this connector apart and check the terminals to make sure they are all in good shape and properly seated. The terminals should be positions 12 (WH wire) and 13 (WH-BL wire)

 

Like 52merc. Were you working on anything just prior to issues?

 

There is a security type module on the passenger side below or behind the glove box that if disconnected will make all kinds or weird things happen. Like others said, were you modifying anything before the problems began?

 

The other place to check would be connector C2431. This is a black connector attached to the Gateway Module which is the module the OBDII diagnostic port is attached to. HS1-CAN is Pin-19 and Pin-20. I would also check the harness running up to the PCM for physical damage. Rodents love the wire insulation used on these trucks.

 

Hey! I really appreciate the reply!! I just pulled this gray connector C210. Both female and male parts look pristine, no corrosion and both ends have terminals that seem to be clicked in all the way.

 

What's the name of this module? How would I find it?

 

I disconnected this C2431 connector and everything looks good. But what should I look for? See if there's voltage at those pins while the battery is connected?

Also, the PCM cable coming from PCM to fuse box looks perfect, no signs of any damage. I also found the two pins on the PCM cable that are supposed to carry 12v and they do.

​​​​​​

 

I wouldn’t put much stock in the comms codes since the ignition turns on and appears to start (“clicks under the hood”) so the BCM and PCM are authorizing a start condition. Sounds like a bad starter/starter solenoid or excessive voltage drop on the power wire to the starter.

 

It's a push button start. If i press it once it starts flashing green and the only thing that changes is that the right headlight turns on. If I press a second time, it turns off. When I press the brake, it turns solid green. The information dash screen only shows the mileage this whole time. Nothing between the tach and speedometer. The only clicking I hear is I think the starter relay. I jumped the pins under the relay and the starter turned, but nothing else turned on.