2011 F-350 XLT CCLB 6.2 256K miles.
Put 4000 miles on it in a week and a half towing a 10K trailer, everything was working great until coming Eastbound over Vail pass. Radiator blew out. Shut it down about 30 feet from where it let go and turned it off. Got towed to home. Cranked engine over to put it in the driveway from the flatbed. No issues, started right up, ran for 20 seconds. No errors on dash. This was Tuesday, 7/18. Go to start it today to move it to fix the radiator, no start.
Symptoms:
1) Dash display cycles through the following errors: "Engine overtemp", "Service Advancetrac", (just a wrench), "Starting system fault", "Hill Descent Control fault", "service advancetrac" (again). When I try to crank, I hear a relay on passenger side kick area, and dash goes black.
2) Snap-on reader cannot connect to ECM.
3) Forscan shows - PCM - Unable to read DTC, APIM - U0100 - Lost communication with ECM/PCM, APIM - U0422:00-2B - Invalid data received from BCM, TCCM - U0100 - lost comm with ECM/PCM, TCCM - U0101-000A - Lost comm with TCM, ABS - U0100, Lost Comm with ECM/PCM, RCM - BCM - U0100 - Lost comm with ECM/PCM, IPC - U0100, IPC - U0424 - Invalid data from HVAC Control Module, IPC - U0462 - Invalid data from Compass Module, IPC - U300A - Ignition switch - Signal plausibility Failure, HVAC - U0401:68-0A - Invalid data from ECM/PCM, HVAC - U0401:82-0A - Invalid data from ECM/PCM - Alive/Sequence counter incorrect/not updated.

Steps taken so far:
1) Checked all fuses
2) Disconnected battery for 15+ minutes
3) Disconnected ECM and reconnected.
4) Checked, but did not dis/reconnect any cables to what I believe is the BCM in passenger kick area
5) Tested engine turns over via starter, cranks fine.

No change thus far.

So I'm looking at bad ECM or BCM, or the wires by parking brake? Anyone else ever seen this? Any thoughts on a cause?

EDIT: Found the issue. Somehow the ground leg from the relay in the engine compartment fusebox was open. How does a wire in a wiring harness go bad from just sitting there?

 

Me personally any kinda issue like that I’m checking simple stuff first. I would look at ground issues being a older truck.

 

also check the ignition switch.
my 2014 would not start by key, but would start by remote fob.
replaced ignition switch and all was good again.

 

Hi, do you have more information on which ground leg from wich relay in fuse box ( BJB) ? I cannot understand why after we removed the power to the PCM ( remove fuse 26 or disconnect the battery cable) all is working good... The ground cable still broken no???? Thanks