The dealership replaced my battery today and gave me my car back. We've been running alternator and battery tests for the past week and everything comes up good. Within 5 minutes of leaving their lot my nav screen shows that I'm having a charge problem and my battery and brake light came on. I thought my car was going into limp mode but luckily it didn't. I took it back to the dealership and they told me not to shut the car off so the foreman and a tech can run some more diagnostics. We saw that the Day time running lights weren't on for most of the hour they were running diagnostics. Then every now and then the pitch of the engine would change and the day time running lights would come on for a bit or flicker.

The foreman said there are 3 wires to the alternator and one of the wires that triggers the warning light on the dash also runs the DRLs. Has anyone heard of this or experienced this also? 03 Sedan, with nav, stock. Thanks