OBD-II Error Code P1418 - Oxygen Sensor Bank 1 Sensor 2 Circuit Low

OBD-II Standard OBD-II Major O2 Sensor

Model: SAE J2012 Extended | Code: P1418

Applicable Systems

OBD-II

Symptoms

The downstream oxygen sensor for bank 1 signal is below expected. Catalyst efficiency monitoring may be affected.

Step 1: Connect an OBD-II scan tool and read all stored DTCs and freeze frame data
All DTCs and freeze frame data are retrieved
Step 2: Inspect the related sensor or actuator wiring for damage, corrosion, or loose connections
Wiring and connectors are in good condition
Step 3: Use a digital multimeter to check sensor voltage, resistance, and reference signals per manufacturer specifications
Values are within specified range
Step 4: Perform component-level testing of the suspected sensor or actuator
Component passes or fails definitively
Step 5: Clear codes and road test to verify repair
Code does not return and system operates normally

To reset code P1418: 1) Repair the underlying fault. 2) Use an OBD-II scan tool to clear the DTC. 3) Perform a drive cycle.

Q: What does OBD-II code P1418 mean?
Code P1418 indicates: Oxygen Sensor Bank 1 Sensor 2 Circuit Low. This is a Toyota manufacturer-specific diagnostic trouble code.
Q: Is code P1418 serious?
Severity: Major. Service as needed.
Q: How do I fix code P1418?
Diagnose the O2 Sensor system and replace faulty components.