Battery and Brake Warning Lights On - DOA Replacement Alternator

Electricalbeginner✓ OP Confirmed

Problem

Battery and brake warning lights illuminated on the dashboard after installing a new alternator from Autozone. The charging system was only producing approximately 12V at the battery with the engine running, and the issue appeared to be RPM-dependent.

Battery warning light onBrake warning light onOnly ~12V at battery with engine running instead of 13-14VRPM-dependent charging behavior

Root Cause

The replacement alternator purchased from Autozone was dead on arrival (DOA). The remanufactured unit was defective out of the box and not charging properly.

Confidence

High confidence — Original poster confirmed this resolved the issue

View Original Thread →Posted May 2021 on SupraForums.com