2014 Focus Unwanted Cranking

[forddieseldoctor]

I had a 2014 Focus that in the event that the key was turned to run without starting the engine and then turned to the off position it would crank for a couple seconds once they key got to the off position. The ignition switch status pid in the bcm showed it switch to crank on the way off and the crank pid in the pcm showed it was getting a crank request signal. 

I performed some basic circuit checks on the crank circuit that goes to the pcm and then I replaced the ignition switch. The concern stayed. 

Once hotline got back to me they swore up and down that I had a short circuit in the crank signal circuit from the switch to the pcm. I unpinned both ends of this circuit and I discovered that contrary to what the workshop manual says, the car will start normally without the crank signal wire. 

After a rather legnthy argument with a hotline guy who insisted that I was full of shit and claimed that I needed to do all my voltage tests at the bcm while looking for a short to power cause it might not show up at the ignition switch end of the circuit, I discovered that the  crank/start wire to the bcm had an aftermarket backup camera tapped into it. I removed the wire and everything was good to go. 

So long story short.... the bcm tells the pcm when the ignition is turned to crank. The same way that it tells all the other modules when to wake up. 

[tonybullitt]

That's good to know. Thanks for sharing. All starting issues on that style for me have been ignition switch housings.

[forddieseldoctor]

The red line on the bottom is the acc/run circuit (in an inverted position so I could see it easier). The orange line is the run/crank circuit. Since the acc/run circuit went to zero volts before the run/crank circuit it thought that the key was being turned to crank.