Common questions

What should voltage be for battery light to stay on?

What should voltage be for battery light to stay on?

Disconnect the two wire box-like electrical connector from the alternator’s voltage regulator and see if there is any voltage (should be around 12 or more volts DC) from the wires going to the alternator. You can try testing this with the engine shut down and the key on, but it may not work on all vehicles.

What should the battery voltage be when the car is running?

The voltage, when the engine is running, should be in the range of 13.5-14.7 volts. When your car is running the cars alternator is charging the battery, this is why you should see a higher voltage. If you’re readings are significantly higher or lower than these then it would indicate a fault with the battery and/or the alternator.

When does the battery warning light come on?

May 25, 2016. The battery light or charging warning light, available on the dashboard of your car, indicates malfunctioning or poor charging of the battery. This light illuminates whenever the charging system does not charge the battery with a voltage above approximately 13.5 volts.

Why does the battery light not come on?

If your alternator is putting out 10-10.5 volts or less means one of the diode pairs are bad, 5-5.25 volts or less 2 diode pairs are bad. Either way the alternator is not charging the battery and it’s the fault of the voltage regulator. Ask the person doing the test if he can tell you what the field voltage is on the alternator.

May 25, 2016. The battery light or charging warning light, available on the dashboard of your car, indicates malfunctioning or poor charging of the battery. This light illuminates whenever the charging system does not charge the battery with a voltage above approximately 13.5 volts.

Can a new alternator run over 14.5v?

Bought a replacement alternator but I am sending it back as I measured and have seen it running over 16.5V. The manual says the regulator should keep it to a max of about 14.5V. I put a brand new and fully charged battery in at the same time the alternator was changed, so I don’t think the battery can be blamed.

When does the alternator light turn on the battery?

On older vehicles, the battery light would turn on the alternator light when the alternator output or battery voltage dropped below a preset value. The battery light on modern vehicles, however, is controlled by data and trouble codes. This is why a scan tool is essential to diagnosing a charging system.

What does it mean when Battery Light comes on while car is running?

When you first turn on your car with the engine off, the battery light will illuminate and this is normal. If the battery light comes on while the engine is running and the vehicle is being driven, this indicates a problem with the charging system. Step 1: Turn off everything that draws power.

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Ruth Doyle