Re: Light and VDC Failures
Yes, you are correct. The battery voltage does not tell the full story. What you need is someone like ATS who use a dirty great big resistor which effectively shorts the battery - the reading can the be more accurate than putting a multimeter on it.
However, even though the reading may indicate that the battery is good, the cars electronics are so sensitive that it could still be the battery.
I for one fell under this category and got so fed up with spending money on trying to 'fix' this issue with dealer resets etc, that I followed someones recommendation on here (a few years back now) on changing the battery...and it worked!
It doesn't work for all, but at £50 or so for a proper brand new Bosch battery, it was well worth the risk.