E-Brake and Battery Warning Lights On Simultaneously After LED Cluster Swap

After replacing all instrument cluster bulbs with LEDs, the e-brake warning light and battery warning light illuminate simultaneously as soon as the e-brake handle is even slightly pulled up. Both lights turn off when the e-brake is fully disengaged, and neither light comes on during normal driving.

The instrument cluster's printed circuit board contains diodes that rely on the specific resistance (ohms) of stock incandescent bulbs to block current flow between circuits. LED bulbs have far lower resistance than incandescent bulbs, so the reverse bias leakage current through the diodes is enough to illuminate the LEDs, causing cross-illumination between the battery and brake warning light circuits.

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