my car battery is flat. I did some measures with a multimeter. I will explain them below. Can anyone please tell me what can be the issue? Note: My car is a VW Polo 9N3 2007
For the last 2 weeks, the battery light on the dashboard does not turn off when I start the car. After I drive for 1-2 min, it turns off. However, 2 days ago, the battery was completely flat, with all electrical components (interior lights, radio, power steering, etc.) on the car stop working (except the headlights, I was driving at night).
- The alternator was replaced 1 year ago, all the gears and belts seem to spin fine.
- Tests with a Multimeter
- Voltage when the engine is off, key is off: 11.6V
- Voltage when the engine is off, key is on: 0V (in fact, few mV is displayed, same for the 0 results I mention below)
- Voltage when the engine is on, the battery light on the dashboard is on: 11.6V
- Voltage when the engine is on, after I ramp-up the engine, the battery light on the dashboard is off: 0V
After these tests, the battery is completely flat, so I cannot do any test anymore :D Please give me some possible reasons.