P0121 – Land Rover DTC

Land Rover DTC P0121 – Throttle Position Sensor Output Signal Error Fault

DTC P0121 meaning on Land Rover

DTC P0121 on a Land Rover indicates a fault with the Throttle Position Sensor (TPS) output signal. The Powertrain Control Module (PCM) detects that the TPS signal is out of range or not responding correctly.

Land Rover DTC P0121 symptoms

• Check Engine Light illuminated
• Reduced engine power
• Poor acceleration response
• Stalling or rough idling

Land Rover DTC P0121 causes

• Faulty Throttle Position Sensor
• Corroded or damaged TPS wiring
• Incorrect TPS calibration
• PCM software issue

Land Rover DTC P0121 seriousness

The DTC P0121 fault code should be addressed promptly as it can lead to drivability issues and potential safety concerns. Ignoring this fault may result in further damage to engine components.

How to diagnose DTC P0121 on Land Rover

1. Use a diagnostic scanner to retrieve the fault codes
2. Inspect the TPS wiring for any damage or corrosion
3. Check TPS voltage output using a multimeter
4. Verify TPS calibration and adjust if necessary
5. Perform a visual inspection of the TPS for any physical damage

How to fix DTC P0121 on Land Rover

1. Replace the Throttle Position Sensor if faulty
2. Repair or replace damaged TPS wiring
3. Calibrate the TPS according to manufacturer specifications
4. Update PCM software if required
5. Clear fault codes and perform a test drive to confirm the issue is resolved

How to erase DTC P0121 on Land Rover

1. Use a diagnostic scanner to clear the fault codes
2. Disconnect the vehicle’s battery for a few minutes to reset the PCM
3. After clearing the codes, perform a drive cycle to ensure the fault does not return

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