StockSH

I turned off my car for one minute and when I try to start the car , there was no response. No dash light (slight hints of light), no lights & No door/trunk lock worked. I cleaned battery terminals & checked voltage with my multimeter. It showed 12.7-8v but it dropped to 4v when I turned the key. (Still no cranking)

Jumping battery made my car alive for 1 minute & car died again (made home by jumping battery 3 times)

My question is “can battery show good voltage while having bad cranking amps?” I didn’t have any signs of weak battery or alternator before this mess.

CYANiDE91

Yes. You can have good voltage under no load (i.e. checking with a meter) and have a bad battery. A true test is done under load (see below).

Step 1 - Battery test (any auto parts store)

flanders

It could be your starter motor that's defective but not likely, 99% sure your battery is bad.

GSteg

Yes. If your battery has built up enough internal resistance, it'll limit the amount of current it can deliver. You need a load tester as said above.

flanders

Starter motor is great load tester

Chuck S

Same thing for me two summers ago. Parked at my daughter's wedding rehearsal and was the last to leave the church parking lot. No start. No one wanted to answer their cell phones either. Push started it (by hand) and, not knowing why it wouldn't start, drove home and put her in the garage for the night and drove my truck to what was left of the rehearsal dinner. Charged the battery all night. 12.7v DC the morning and still no start. Battery voltage dropped down below 6v when the started tried to crank the engine. Bad battery, simple as that. A $5 multimeter and the starter will do the same job as a $20 battery load tester. Any voltage drop below about 9vDC is unlikely to crank the car.

-- Chuck

Car Analogy

This. The test you did clearly shows battery can't keep up with the load.

If you stacked two 9v smoke alarm batteries together, they'd read 18+v. More than enough to start your car, right? Guess what that volt meter will read when you try to crank it over?

That is sorta what is happening with your cars battery.

GSteg

Indeed...if it was working properly. A faulty starter will draw more amps than it's supposed to. I had someone with a Lexus ES330 come to me with similar issues where the battery voltage would drop a decent amount when I tried to crank it. I pulled the battery off the car and put it on a load tester and while it wasn't great, it wasn't on its last leg either. I pulled the starter off the car and found the brushes to be near the end of its life and had accumulated quite a bit of dust in there. Replaced the starter and had no problem since and the battery is still going, although I did recommend to have it replaced just in case.

However, OP's case does point to a faulty battery.