Thanks to this thread, I started to suspect that it was my battery causing the issues that I was having (1. Random errors (Parking Brake Auto Off not functional, HDC (Hill Descent Control) system fault), ect. and 2. Backup sensor would only work 1/5 times you started the truck).
Last Wednesday I had it tested at Advance Auto, and the test showed that the battery only had about 225 CCA left out of the 720 the International Battery was supposed to have. It also said that the battery needed charged, even though I had just driven 40 minutes in city traffic. I had planned on keeping an eye on the battery and replacing it next month...
It had other ideas. Went out Saturday to go pick up some supplies for work around the house and the truck wouldn't start. Battery had enough juice to do the self diagnostic and run the radio, but it wouldn't even try to crank. After jumping it with the van, I threw some tools in the truck and went over to Advance Auto and replaced it with an
Advance Auto Gold AGM battery. Night and Day difference in starting now vs how it has been over the past few months. Turn the key and it is on. All errors are gone, and the backup sensor system hasn't failed to turn on once. I'm kind of kicking myself for not changing the battery a while ago. In a week, I am going to go back and have the test run again to test the alternator. I will also measure the voltage on the battery tonight when I get home.
I am a little worried about the alternator, my wife's car a few years ago had a battery that acted just like this one. It was bad, so we replaced it. A few weeks later the battery was going dead again. The alternator had an internal fault that caused it to only charge some of the time.