Battery pic/visit workshop
Should I just take it to the dealership and let them figure it out or keep replacing parts till it goes away?
check voltage at both batteries and alternator with a meter.
if all check out then.......
check fuses front and back
check voltage regulator at alternator
check BCM battery control module




The last thing you want it to be is the alternator, which is $400 and involves taking half the engine apart.
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Shops that only sell batteries should have one of those accurate conductance testers some of them can test alternators aswell. This will give you a yes or no if the batteries are an issue.
Then look at the alternator if its melted at the back the rectifier pack has been overloaded. If you pull the voltage reg and its like the pictures on here that "might" of been your issue. But id still test everything else aswell while your at it as this ends up a compounding thing where it costs more and more money if you dont get it right the first time.
14v is with the car running on the MF display.
12.2 not running is about right when you use the MF display to tell you voltage as there is a voltage drop in the line between the batteries and that display. So its actually more like 12.6 at the battery with a multimeter.
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Last edited by austingtir; Apr 24, 2014 at 08:06 PM.


