Light Failure Sensor Corrosion Fix - Cleaning, Bypass, or JDM Replacement (89373-20070)

Electricalintermediate✓ Community Verified

Problem

The rear light failure sensor (part number 89373-20070) located in the rear hatch area becomes corroded from water intrusion through a deteriorating rear hatch seal, causing false 'Lights' warning readings in the gauge cluster and unreliable tail/brake light failure detection.

False 'Lights' warning indicator on gauge clusterUnreliable rear light failure detectionVisible corrosion inside the light failure sensor boxWater intrusion into rear hatch area where sensor is mounted

Root Cause

Water leaking past the rear hatch seal corrodes the circuit board traces inside the light failure sensor unit, causing false readings and eventual failure of the sensor.

Confidence

Moderate confidence — Multiple community members agreed on this solution

View Original Thread →Posted August 2022 on SupraForums.com