OBD-II FAULT CODE
B2509
Rear Fog Lamp Switch Circuit Failure
Meaning, symptoms, likely causes, diagnostic checks and repair guidance for B2509.
- Body/accessory warning lamp or feature not working
- Blown bulb/LED module
- Poor ground
- Fuse/relay fault
- Switch/module/wiring issue
- Check related fuses, connectors, grounds and switch/module power supply
- Check bulb/module, fuse, ground and connector corrosion
- Replace failed bulb/module, repair ground/wiring, replace switch/relay if confirmed
Related Codes
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Disclaimer: Information is provided for general guidance only and may not apply to all vehicles. Always consult a qualified technician.