[Non Corsa] Low voltage

[jt999]

Vegas' thread reminded me to post this.

A few times recently I've found the Saxo battery to be dead when I try to run it. My stereo has a volt meter built in and suggests that with lights on and engine running I have around 10.4v which doesn't seem right as I guess I'm using more power than the car is generating? If I turn off the lights I have maybe 13.3v.

I guess it's alternator but I have no idea, I just want it to work for a few more months

[Rocksta]

Measure it of the battery.
I'm guessing your headunit isn't calibrated or the earth might not be fantastic.

If it is still reading the same when the lights are on then your alternator is probably ready to be replaced.

[Taurus]

Could be a short in the lighting causing the voltage to drop.

[walksall]

Not sure that our built in voltmeter is intended to be much more than a guide, so maybe a better instrument is called for.
That said, the built in meter can't be that bad, as it is indicating low battery voltage, which you are proving by having a flat battery.

Regards.