P1121 – Honda DTC

Honda DTC P1121 – Throttle Position Lower Than Expected

DTC P1121 meaning on Honda

1. DTC P1121 indicates that the throttle position sensor is reporting a lower voltage signal than expected by the Engine Control Module (ECM) on a Honda vehicle.

Honda DTC P1121 symptoms

• Check Engine Light (CEL) illuminated on the dashboard.
• Reduced engine power or acceleration response.
• Engine may hesitate or stall during acceleration.

Honda DTC P1121 causes

• Throttle position sensor malfunction.
• Wiring or connector issues in the throttle position sensor circuit.
• ECM software or hardware problems.

Honda DTC P1121 seriousness

1. If left unresolved, DTC P1121 can lead to drivability issues and potential safety concerns due to erratic engine performance.

How to diagnose DTC P1121 on Honda

1. Use a diagnostic scanner to retrieve the trouble codes and freeze frame data.
2. Inspect the throttle position sensor and its wiring for any visible damage or corrosion.
3. Perform voltage and resistance tests on the throttle position sensor according to the manufacturer’s specifications.

How to fix DTC P1121 on Honda

1. Replace the throttle position sensor if it fails the diagnostic tests.
2. Repair any damaged wiring or connectors in the throttle position sensor circuit.
3. If necessary, reprogram or replace the ECM to address any software or hardware issues.

How to erase DTC P1121 on Honda

1. After completing the repairs, use a diagnostic scanner to clear the trouble codes and reset the Check Engine Light.
2. Ensure that the vehicle is in proper working condition by performing a test drive to verify the repair.