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Discussion Starter #1
I have gone through the pain of replacing my alternator (which had bad diodes according to the rebuild shop) and the cable since it showed wear and tear (fraying near the alternator connector).

Now I am getting sporadic flashes of the battery light on the dash - I check the secret menu option #9 and see that I am getting a voltage at idle of 13.5 / 13.6 v which seems normal. I trickle charged the battery just prior to hooking up the starter.

I want to understand what might be causing the dash light to flicker (like on for a second then off for a while then back on for a second - not a constant flicker). I would like to have my electrical working so I don't strand myself somewhere.

At this point the only "old" element is the battery which has been through a number of charge cycles (flat up to charged). I have a 10/6/2 charger and it does seem to take and hold a charge when I trickle it, but I don't rule out that the issue with the dash light is the battery.

If someone knows how it works and the best way to diagnose my issue, I would be happy to finally have the car back in running shape.
 

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Monitor the voltage on the secret menu when the light flashes. Does it drop? It should.

The dash light is driven by a module in the alternator. It's not a battery problem.
You may have the same problem I did - a loose connector. When you drop the alternator to remove the 3-pin connector on the back, it pulls on the wires and can disconnect the next 4-wire connector up the line which is under the plenum on the LHS. It's connector X6054 below. It can be accessed without removing the plenum. Or the wiring could be damaged inside the insulation.

I found out by pulling the alternator again, disconnecting the connector, and testing for 12V at pins 1 and 2, with ignition on.

Alternator.JPG
 

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Discussion Starter #4
Drove around a again and this time it seems to keep the light off. I will definitely look at the connector you suggest 68FB. Removing the alternator in my car is epic due to all the stuff that I have in the way that is not present on a stock car. I know that the alternator tugged on some wires coming out, so this is a good explanation. I will drive around with the secret menu on to make sure I am getting proper charging voltage.
 
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