My car is normally used just 3 days a week so I have a routine of putting the battery on a quick top up charge at the weekend. I have an old Gunson automatic charger with an ammeter. With doing this on a regular basis you get to know the battery by observing how the the charge current falls as the battery gets towards full charge. Last weekend the charge current didn't drop below 0.5 Amps as it usually does and subsequent monitoring of the voltage showed there was definitely a problem with either the battery failing or I had something like a 0.5 Amp a discharge from a bit of electronics that wasn't shutting down.
To find out I disconnected the battery then fully charged it. Checking the voltage after 24 hours rest I read 12.76 volts which is not bad at all for a old non AGM battery. I was sort of hoping it would have been the battery which is at least a simple replacement and it's due anyway. Tracing a current draw was going to be a pain and I didn't have time as I had to use the car the next day, so I connected the battery back up.
Even before I drove the car a voltage check after 24 hours showed the problem had gone away all on it own and that was later confirmed with another check today. Result - those are the sort of problems I like. I can only think that having the battery disconnected for a time has reset something.
For what it's worth the only things that needed attention after a 24 hour battery disconnection were the time and date had to be reset and the MPG figure for the previous period of driving was lost (but not the trip meter reading). I haven't tried the windows yet.
To find out I disconnected the battery then fully charged it. Checking the voltage after 24 hours rest I read 12.76 volts which is not bad at all for a old non AGM battery. I was sort of hoping it would have been the battery which is at least a simple replacement and it's due anyway. Tracing a current draw was going to be a pain and I didn't have time as I had to use the car the next day, so I connected the battery back up.
Even before I drove the car a voltage check after 24 hours showed the problem had gone away all on it own and that was later confirmed with another check today. Result - those are the sort of problems I like. I can only think that having the battery disconnected for a time has reset something.
For what it's worth the only things that needed attention after a 24 hour battery disconnection were the time and date had to be reset and the MPG figure for the previous period of driving was lost (but not the trip meter reading). I haven't tried the windows yet.
