starting problem

There is no master circuit breaker. Did it start with a jump? You may have a battery drain. 12.0 volts doesn't mean the battery is good it can have voltage with low amps available you need to test it when it doesn't start to know for sure, but start by checking to see if anything is staying on like a glove box lite, dome lights, cig lighter, anything that works with the switch off. I hope this helps take care

Thanks Mike. Voltage measured 12.5V. Jumpstart didn't work. Nothing working with the switch off or on. Is there one high current fuse that might do this? or a relay?

Look at the starter solenoid. There are a bunch of fuse links on the battery stud there, first take them off and feel them through the insulation then pull on them if you feel a break or the wire stretches apart you found it. The solenoid is mounted on the fender well close to the battery. Replace with a fuse link of the same size. If the problem isn't there start moving and pulling harnesses around, don't move to fast or you'll lose the exact place and end up cutting into looms you don't need to. These types of opens are usually easy to find because it affects so many circuits.

Follow up: Problem was from an open electric circuit caused by corrosion at the end of a battery cable. About six months ago a new cable clamp was attached to the end of the negative battery cable. Now when the new battery was installed, the battery cable clamps and new battery terminals were wire brushed as usual, but the corrosion where the battery cable attached to the clamp was not visible because the attachment point of cable to clamp was covered. AAA mechanic diagnosed the problem, removed and cleaned the cable end and reattached it to the clamp which solved the problem.