Join Date: Jun 2005
Location: Jerez de la Frontera in Cadiz, Spain.
I have the same issue. I think it's down to the gauge. When testing with a multimeter as Steve suggests I get 2 volts higher at the fuse than what I get on the gauge. Prior to start up with key in ignition at first position and after the test sequence, I get about 10 volts at the gauge. Testing at the fuse, I get 12.5 or thereabouts and I think about 13 or 14 (been a while) with engine running but only 12 at the gauge. I've had it like this since I got it and never had a battery/alternator problem which is why I believe it's the gauge itself that's off.
Past glories: Sud ti, Alfetta GTV, GTV6, 33 ti, 33 ie, 164 V6, 164 V6, GTV TS, 156 TS, Alfa 159 2.4 Q-Tronic JTDm
Now: 164 V6 24v Zender Alfa Sport (QV Mod)