BATTERY LOW; LOST CHARGE; IS IT BATTERY OR CHARGFING SYSTEM?
Jan 10, 2012 at 2:33 AM
HOW DO I CHECK IF THE ALTERNATOR IS WORKING?
2005 BMW X5
WALT
- MEMBER
- 1 POST
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CARADIODOC
- ✓ASE Certified Mechanic
- 34,321 POSTS
Measure the battery voltage with the engine off and with it running. Off must be 12.6 volts. If you find 12.0 volts, it's okay but discharged. Closer to 11 volts means a cell is shorted and the battery must be replaced.
Engine running, the voltage must be between 13.75 and 14.75 volts. If it's low, suspect the generator.
Engine running, the voltage must be between 13.75 and 14.75 volts. If it's low, suspect the generator.
Jan 10, 2012 at 2:39 AM
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