The problem started a while ago, when it would progressively crank slower and slower. Now it just won't start. I had figured the battery was going - apparently, that's not it.
All it does now is click the solenoid when it's in the car.
I tried jump starting it - just a click.
I tried bypassing the switch and running a hot lead from the battery straight to the starter - just a click.
I took the battery and starter to Auto Zone and had them tested. They both tested good. The battery tests at almost 13v w/o a load, and holds at almost 11v with a load. The starter engaged and turned during the test.
When I put the charger on the battery, it is in charge mode for less than a minute and it reads full charge.
I've checked and double checked all the connections and grounds, and all seem ok. The cables appear to be ok.
When I bench test the starter at home, it engages and turns, but it sounds like it's winding up slowly. This is unlike other starters I've tested in the past that engaged and spun very quickly.
I have had older Ford solenoids seize in the past and just click, and when you smack them with something, they freed up. I tried it with this, to no avail. It still just clicks.
I don't know what else to test, or where to go from here.
I should have asked at Auto Zone - does their tester test the solenoid or just the starter?
I don't know what to look at next. Any ideas?