P0161Toyota TundraYears: 1996 - 2026
O2 Sensor Heater Circuit Malfunction (Bank 2, Sensor 2)
Reviewed by ASE Certified Technician
What does this mean?
Code P0161 indicates a problem with the downstream oxygen sensor on Bank 2. This sensor monitors catalytic converter efficiency on Bank 2.
Disclaimer: This diagnostic code is part of the standard OBD2 system and can apply to Toyota Tundra models manufactured from 1996 to 2026. However, please note that the presence of this specific code depends on your vehicle's exact engine configuration, options, and production year.
Advertisement (In-Article)
Common Causes
Faulty oxygen (O2) sensor
Failed O2 sensor heater circuit
Damaged, chafed, or broken wiring harness
Exhaust leak before oxygen sensor
Failing or clogged catalytic converter
Symptoms to Watch For
- Check Engine Light is illuminated
- Decreased fuel economy
- Failed emissions test