P1121 – Jaguar DTC

Jaguar DTC P1121 – Throttle position (TP) sensor/mass air flow (MAF) sensor – implausible signal

DTC P1121 meaning on Jaguar

1. DTC P1121 indicates an implausible signal between the throttle position (TP) sensor and mass air flow (MAF) sensor on a Jaguar vehicle.

Jaguar DTC P1121 symptoms

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

Jaguar DTC P1121 causes

• TP sensor or MAF sensor malfunction.
• Wiring or connector issues between the sensors and the Engine Control Module (ECM).
• ECM software or hardware problems.

Jaguar DTC P1121 seriousness

1. If left unresolved, DTC P1121 can lead to poor engine performance, reduced fuel efficiency, and potential drivability issues.

How to diagnose DTC P1121 on Jaguar

1. Use an OBD-II scanner to retrieve the specific fault code and freeze frame data.
2. Inspect the TP sensor and MAF sensor for any visible damage or contamination.
3. Check the wiring harness and connectors for signs of corrosion, damage, or poor connections.
4. Perform sensor testing and voltage checks according to the manufacturer’s service manual.

How to fix DTC P1121 on Jaguar

1. Replace the faulty TP sensor or MAF sensor if either is found to be defective.
2. Repair or replace any damaged wiring or connectors between the sensors and the ECM.
3. Update the ECM software if necessary.
4. Clear the fault code and perform a test drive to ensure the issue is resolved.

How to erase DTC P1121 on Jaguar

1. Use an OBD-II scanner to clear the fault code from the ECM memory.
2. Ensure the repair has been completed successfully before clearing the code.
3. If the fault returns after clearing, further diagnosis and repairs may be required.

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