P1121 – Mazda DTC

Mazda DTC P1121 – Throttle Position Sensor Signal Not Consistent with Mass Airflow Signal

DTC P1121 meaning on Mazda

DTC P1121 on a Mazda indicates that the Throttle Position Sensor (TPS) signal is not consistent with the Mass Airflow (MAF) sensor signal. This means that the engine control module (ECM) has detected a discrepancy between the expected values from these two sensors.

Mazda DTC P1121 symptoms

Symptoms of DTC P1121 on a Mazda may include:

• Check Engine Light (CEL) illuminated
• Reduced engine power
• Poor acceleration
• Engine stalling or hesitation

Mazda DTC P1121 causes

Common causes of DTC P1121 on a Mazda include:

• Faulty Throttle Position Sensor (TPS)
• Issues with the Mass Airflow (MAF) sensor
• Wiring or connector problems in the TPS or MAF circuits
• ECM software issues

Mazda DTC P1121 seriousness

DTC P1121 should be addressed promptly as it can lead to drivability issues and potential engine damage if left unresolved. Ignoring this code may result in poor performance and fuel efficiency.

How to diagnose DTC P1121 on Mazda

To diagnose DTC P1121 on a Mazda, you can:

1. Use a diagnostic scanner to retrieve the trouble codes
2. Inspect the Throttle Position Sensor (TPS) and Mass Airflow (MAF) sensor for any visible damage
3. Check the wiring and connectors for corrosion or loose connections
4. Perform a voltage test on the TPS and MAF sensors to ensure they are functioning within specifications

How to fix DTC P1121 on Mazda

To fix DTC P1121 on a Mazda, you may need to:

1. Replace the Throttle Position Sensor (TPS) if faulty
2. Replace the Mass Airflow (MAF) sensor if it is malfunctioning
3. Repair any damaged wiring or connectors in the TPS or MAF circuits
4. Update the ECM software if necessary

How to erase DTC P1121 on Mazda

To erase DTC P1121 on a Mazda, you can:

1. Use a diagnostic scanner to clear the trouble codes
2. After fixing the underlying issue, drive the vehicle to allow the ECM to relearn the sensor values
3. Ensure that the Check Engine Light (CEL) does not reappear after clearing the code

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