The B1360 code on your 2021 Lexus RX indicates a malfunction in the auto-dimming mirror system. This code affects your RX's electrochromic mirror(s), signaling the system cannot properly darken the mirror to reduce headlight glare from vehicles behind you.
Understanding B1360 on Lexus RX
Auto-dimming mirrors use electrochromic technology that darkens the mirror glass in response to bright light from behind. The system includes sensors, control electronics, and the dimming element. Code B1360 indicates a fault has been detected in this system.
Common Symptoms
- Mirror doesn't dim automatically
- Mirror stuck in dimmed state
- Inconsistent dimming
- Green power light not illuminating
- Outside mirrors not dimming (if equipped)
- Dimming feature works intermittently
Primary Causes
- Auto-dim mirror internal failure
- Light sensor failure
- Mirror wiring/connector issue
- Outside auto-dim mirror failure
- Body ECU communication fault
- Power supply issue to mirror
Diagnostic Procedure for 2021 Lexus RX
Using Lexus Techstream or compatible scan tool, access mirror system data. Check if sensors are detecting rear light. Verify power and ground at mirror connector. Test manual dim override if available. Shine a light at the rear sensor to test system response. Check if outside mirrors dim (if equipped with auto-dim).
Repair Solutions
Replace failed auto-dimming mirror assembly (interior and/or exterior as needed). Repair wiring or connector issues. Auto-dim mirrors are typically replaced as complete units since the dimming element is integrated. Clear codes and verify proper dimming response to bright light from behind.