Battery

[Juz]

Hi Guys,
Been having problems with my battery in my 2014 Spain build d40. I put a new battery in it and seems to be not falling charging to no more then 12.4 volts when driving more then an hour and the dash cam I have it turns off right away and have had problems starting it too at times. Is 660 cca the right one for it cause I’m not sure and battery world seems to thing it is.

 

[Old.Tony]

660CCA is enough cranking power, but the more the merrier - I've got a Century 910CCA battery in mine.

The 2014 cars had a "smart alternator", which would come on long enough to restore the energy taken to start the car but then would switch off. This plays havoc with dual battery systems and has prompted many an owner to disconnect the green wire on the alternator (which turns off the smart function). You might consider doing the same - but try gently removing it, rather than using something like wire cutters - you might need to put it back!

You might want to monitor the voltage immediately after starting. It should rise to over 14V for a short time. If it doesn't, there's a chance your alternator is not functioning properly any more.

 

[Juz]

Ah so that would be why it’s only charging to about 12.45 about how long would it take the dash cam to discharge that too 11.99? A multimeter shows 14.28v when the Ute is running.

 

[Old.Tony]

A dashcam would use hardly any power. 5v at 500mA would be its absolute peak, and that's just 2.5W (or about 0.2A at 12V). So if you have a typical 70Ah (say) battery, you'd need to leave the dashcam on for 140 hours (almost a week) to run the battery that low (just with that device). There are other power users too though - the ECU, the BCM, the instrumentation ... and batteries have a natural self-drain which gets worse as they age. Mistreatment (too much depth-of-discharge) magnifies the problem. I'd be looking at disconnecting the green wire.

Calculation: 12.45V is about 80% capacity, 11.9V is about 40%, so you're using 40% of 70Ah or 28Ah at 0.2A per hour = 28/0.2 = 140 hours.

 

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on starting voltage at 14+ is normal after about hr of driving volt drops should drop backto just under 13 v . hard starting , is your motor turning too slow when cranking , starter may be on its way out or bad connections , if battery is fully charged turn on headlights have some one check to see if they dim a bit when you crank engine , feel your battery leads and solenoid& bat connection to see if it gets hot, careful i got nasty burn from my kill switch connection