Aston Martin V8 Vantage battery draining.
Discussion
Measure the steady state current draw at the +ve battery lead next to the battery terminal when the car is closed and locked, looping in an external ammeter or using a current clamp and reading the display through the window after a few minutes.
That gen Aston should see an approx 60-90mA parasitic draw, it is largely used powering the alarm. This equates to 1.4 to 2.3Ah battery capacity loss per day, meaning a new 100Ah battery, fully charged should last 3-5 weeks before parasitic discharge presents a problem for starting.
For a new, fully charged 100Ah battery to discharge in a week there would have to be ~ 250-300mA of continuous parasitic loss, 7Ah a day, that’s 50Ah in a week, half the capacity of the battery and significant voltage drop and CCA capacity loss, and it would be rapidly downhill from there.
If you are seeing that sort of parasitic, as has been mentioned, a principle suspect would be the tracker, which can ‘call home’ continuously as a failure mode. Odd that that hasn’t been long resolved though.
Other potential are a defective new battery, even new batteries can fail pretty much instantly, and perhaps you may not be fully recharging the battery before leaving the car standing - alternators work well to charge a battery rapidly to approx 70-80%, but after that the batteries internal resistance increases and charging slows down. To get to 100% this takes a decent run out or a couple of days on a typical charger.
If it’s the tracker, a decent independent will disable it for you.
Good luck.
That gen Aston should see an approx 60-90mA parasitic draw, it is largely used powering the alarm. This equates to 1.4 to 2.3Ah battery capacity loss per day, meaning a new 100Ah battery, fully charged should last 3-5 weeks before parasitic discharge presents a problem for starting.
For a new, fully charged 100Ah battery to discharge in a week there would have to be ~ 250-300mA of continuous parasitic loss, 7Ah a day, that’s 50Ah in a week, half the capacity of the battery and significant voltage drop and CCA capacity loss, and it would be rapidly downhill from there.
If you are seeing that sort of parasitic, as has been mentioned, a principle suspect would be the tracker, which can ‘call home’ continuously as a failure mode. Odd that that hasn’t been long resolved though.
Other potential are a defective new battery, even new batteries can fail pretty much instantly, and perhaps you may not be fully recharging the battery before leaving the car standing - alternators work well to charge a battery rapidly to approx 70-80%, but after that the batteries internal resistance increases and charging slows down. To get to 100% this takes a decent run out or a couple of days on a typical charger.
If it’s the tracker, a decent independent will disable it for you.
Good luck.
Many thanks for the replies. They are appreciated!
The BR clip on the subject explains it really well. Hopefully that will be the issue and I'll phone AJ Tech when they are next open and get the car booked in.
We've previously had the same symptoms on an Audi TT which proved to be a very long, expensive and frustrating road which we never got to the bottom of.
Fingers crossed!
The BR clip on the subject explains it really well. Hopefully that will be the issue and I'll phone AJ Tech when they are next open and get the car booked in.
We've previously had the same symptoms on an Audi TT which proved to be a very long, expensive and frustrating road which we never got to the bottom of.
Fingers crossed!
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