Alternator warning light actually functions as a brake pedal application reminder Options

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Good morning gentlemen, hope it’s been a good week so far.

My alternator warning light goes crazy anytime I step on the brakes or use a turn signal. I confirmed that I’ve got 13.6 V at the battery with the car running, so it appears that I have a wiring issue somewhere, most likely behind the dash I assume.

I was hoping to see if anyone’s had a similar issue and what they did to resolve it to help narrow my focus before I start digging in.

Thanks!

[GregAmy]

The alternator circuit is a very simple one: one side of the bulb connect to the alternators D+ terminal, the other side connects to system voltage at fuse S9. S9 runs most of your gauges, too.

If there's a differential voltage across the bulb - for example, the alternator isn't putting out (0 volts) but the battery still has voltage (12V) - then the bulb lights. If there's no differential voltage - alternator is putting out 13.5V and alternator is putting out 13.5V - then the bulb stays extinguished.

Your goal is to find out where that differential is happening when you engage the brake lights and fix it. My guess would be it's related to dropping voltage at fuse S9.