Correct battery voltage ?

[groar]

Hi,

Yesterday I stopped my car but couldn't close the car with the remote, so I closed it manually.

When I came back to the car, I couldn't use the remote to open it so I opened it manually. But when I put the key in, nothing light on, nor on position I, nor on position II. A colleague of mine said me the battery was dead. I replied I found that strange as usually you don't have enough power to start the engine, but some systems light on correctly. He replied his last battery change was after such an event.

Nobody had in his car any cable to connect two batteries of two cars and start the car with the low battery (mine in this case), and anyway it was late. We went to buy a brand new battery at 1 km in a gas station with a little market. Back to the car, another colleague had some tools in his car to detach the battery and swap it with the new one. Once attached, the new battery gave life back to the car

I looked in a book from a third party () and it describes my battery as a 12V 70Ah. The one I bought is a 12V 50Ah as the previous one. I don't think the missing Ah is at fault.

Tonight I verified the voltage of the old battery (3-4 years old iirc) and it's 12.64. The voltage of the new one is 12.86. Suddenly I'm feeling like the old battery isn't dead...

I'm trying to explain miself what happened, but I can't. I don't understand why suddenly nothing worked anymore. May be something went bad when I switched off and a security activated. When the battery was disconnected and reconnected, the system was reseted and worked again. May be just by disconnecting and reconnecting the old battery I may have reseted everything which could then started again...

Have you already seen that ?
Do you have an explanation ?
What is the correct battery voltage ?

If the battery isn't dead then I think I may build a little independent photo-voltaic or wind system Well, when will have paid the big PV system

Thanks in advance,

Denis.

[ankit]

Swap the old one back in (or just disconnect the cables and hook them up to the old battery while you just lay it down in your engine bay) to see if it starts up. Normal voltage is anywhere from 11.7-13.5 V I THINK.

[dremd]

No load Battery voltage is typically 12.7Volts +- .7

While cranking you should see >10volts

While running should be around 14volts

Load test both batteries (In the states most parts stores will test them for free)

If the load test comes back good, check the voltage inside the car.