LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Honda >> 2017 >> Pilot EX, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTC Diagnostics (4 Of 6) >> DTC Troubleshooting >> DTC P1172, P1174
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC P1172, P1174

DTC P1172  : Rear A/F Sensor (Bank 1, Sensor 1) Circuit Out of Range High

DTC P1174  : Front A/F Sensor (Bank 2, Sensor 1) Circuit Out of Range High

NOTE: 

DTC Description Confirmed DTC Pending DTC Freeze Frame
P1172 Rear A/F Sensor (Bank 1, Sensor 1) Circuit Out of Range High      
P1174 Front A/F Sensor (Bank 2, Sensor 1) Circuit Out of Range High      

DTC (PGM-FI)

  1. Problem verification

    - 1. Turn the vehicle to the ON mode.

    - 2. Clear the DTC with the HDS.

    - 3. Start the engine.

    - 4. Hold the engine speed at 3, 000 rpm without load (in P or N) until the radiator fan comes on, then let it idle.

    - 5. Monitor the OBD STATUS for P1172 and/or P1174 * in the DTCs MENU with the HDS.

    DTC Description OBD STATUS
    P1172 Rear A/F Sensor (Bank 1, Sensor 1) Circuit Out of Range High  
    P1174 Front A/F Sensor (Bank 2, Sensor 1) Circuit Out of Range High  

    Does the HDS indicate FAILED?

    YES 

    Replace the A/F sensor (Sensor 1) .

    NO 

    If the HDS indicates PASSED, intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the A/F Sensor (Sensor 1) and the PCM. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/on-board snapshot - Refer to: How to Troubleshoot the Fuel and Emissions Systems . If the HDS indicates EXECUTING, keep driving until a result comes on. If the HDS indicates OUT OF CONDITION, go to step 1-4 and recheck.