I drive a 2004 VW Passat B5. Recently, my insurance company came round to fit a black box to my car as part of the terms and conditions of my car insurance policy. Whilst they were doing this they had to visually check the condition of the car, as well as check the state of the battery.
A concern that they had to raise on the report was that the battery was in poor condition and that I should consider getting it replaced. If I don't, they said the car may not start reliably in cold weather.
I saw the following reading:
REPLACE BATTERY
Battery State 52%
12.3V
226 CCA
What does this mean? Does my battery really need to be replaced?