Won't crank issues.

Strange problem, hoping for good advice. Problem all of a sudden one morning.
It's probably familiar to some... one-click no-start problem I've read about.
Multimeter shows battery at 12.4, 12.5V. I cleaned the terminals.
I've removed some fuses and relays at the fuse-box. They look ok, & what I could test looks ok.
With headlight stalk turned fully on, I have no headlights, but hear a faint buzzing which
I think comes from the a relay in the fuse-box, but can't pinpoint due to everything being located so closely together.
Interior lights randomly go from somewhat normal to dim while I'm trying the stalk and ign key. Dash lights go from somewhat normal to dim or none.
Auto trans. repld. about 1500 miles ago, all seems fine there so far.
I haven't cleaned any grounds or other terminals, etc. yet. Haven't beaten on the starter yet. Haven't inspected pos. or neg. cables. Transmission also can't be shifted from Park position. Sometimes felt chattering? from integration relay (behind interior fuse access), but not always.
I'm not unfamiliar with mechanics, etc. but need to narrow down the possibilities here. That transmission blew my account away, so I sure could use some free advice.
Thanks!

 

Sounds like the solenoids in the starter to me. Good luck.

 

Start at the power source

Clean the battery terminals and posts they should be shiny not a dull grey

Remove and clean the ground cables both ends .

Your relay making noise is most likely from a low voltage condition.

With a open fuse nothing happens when trying to energize the circuit

A bad starter solenoid would not cause all the other issues

 

Good point Wyoming. I was thinkin' maybe the OP had a starter problem as well as some other problem, but it was more of a guess than anything.

 

I had some Corroded battery cables that caused some similar issues. Like they said above, start at battery and work your way back. Cables would be the next in line.

 

Thanks for the ideas, but, it was the Optima battery which was 10 years old!
I have read about a battery showing good voltage, but not delivering.
That's what it was. Anyway, now some maintenance stuff got done and it's all the better.

 

Well that must have been one of the older ones

Seems the new ones have really gone down hill