Just got back from AutoZone, they tested the battery/alternator and said everything was fine and told me I didn't need a new battery.

What we noticed is that when I turn the key the first time, battery voltage drops down to the low 11 volt range, but after about 10 seconds it slowly crawls back up to the low 12 volt range (no GP light ever). If I turn the key off and then back on again, the GP light comes on and the voltage never drops down into the 11 V range.

What would explain the drastic drop in voltage the first time, but not the second (assuming the battery was tested properly by the AZ guy)?

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-justin

1987 300TD, 1987 300TD
2008 R32, 2000 Passat Wagon