Hi All,

Yesterday morning I left home and everything was normal. After driving 30 minutes on the highway, I stopped off to pick up an order. It took me about 20-30 minutes. When I got back the headlights were on (I had left the keys in as my wife was with me). They are LED ones I put in a few years back. The car wouldn't crank and I heard the clicking sound. I turned on the dome light to see and it was flickering when turning the key. I got out my portable battery booster and started it up. After driving for an hour to another location, I had the same issue and resolved it using the battery booster. I used the booster 5 times before I got home.

Last night, I used a battery charger to charge the battery, and this morning the 4R started right up. The battery was manufactured 4 years ago and is the Walmart brand. I have had zero issues before. Here are some other observations:
1.) Liquid levels in all 6 cells are about 3/4" - 1" below surface.
2.) 12.70 V this morning after fully charging overnight.
3.) 14.35 V when the vehicle is running (with all accessories and lights on and off).
4.) 12.85 V right after the vehicle is turned off.
5.) Used the $20 Harbor Freight battery load tester with a 10 second load and I get 11 V (on the dial it shows up as very slightly weak).

So it seems the alternator is fine, and the battery is okay. I don't understand why the battery didn't charge after an hour of running. What next?