I'm tired of working on it in the dark, so just charging it so I can troubleshoot with the ignition on in the morning.

 

In Eng mode with a good battery fully charged and engine not running the voltage should be 1.2-12.7v. Once the engine starts and the alternator is charging it should show like 14.5 volts.

 

Keep in mind the PCM monitors and controls the internal regulator of the alternator and the charging voltage can vary, based on some factors. Ford does not give a generic voltage value for troubleshooting the charging system but, instead, uses the commanded output and the actual output as part of the troubleshooting.

 

Alternator was replaced. Repair shop says the old one was damaged by an oil leak. I paid for a leak diagnostic before I remembered that I leaked three quarts of oil onto the engine several years ago when the oil fill cap came off while driving on the freeway.

Battery voltage is 12.0 volts while stopped and 14.4 volts with the engine running. The auto stop/start feature works all the time now.