P1400 – Lexus DTC

Lexus DTC P1400 – Sub-TP Sensor Malfunction

DTC P1400 meaning on Lexus

DTC P1400 on a Lexus indicates a Sub-Throttle Position Sensor Circuit Malfunction. This fault code is triggered when the Engine Control Module (ECM) detects an issue with the sub-throttle position sensor or its circuit.

Lexus DTC P1400 symptoms

• Check Engine Light (MIL) illuminated on the dashboard
• Reduced engine performance or power
• Engine may hesitate or stumble during acceleration
• Increased fuel consumption

Lexus DTC P1400 causes

• Defective sub-throttle position sensor
• Wiring or connector issues in the sub-throttle position sensor circuit
• ECM (Engine Control Module) malfunction

Lexus DTC P1400 seriousness

The DTC P1400 fault code should not be ignored as it can lead to poor engine performance and potentially affect fuel efficiency. It is recommended to address this issue promptly to prevent further damage to the vehicle.

How to diagnose DTC P1400 on Lexus

1. Use an OBD-II scanner to retrieve the specific fault code (DTC P1400)
2. Inspect the sub-throttle position sensor and its wiring for any visible damage or corrosion
3. Check the connector for proper connection and signs of damage
4. Perform a voltage test on the sensor to ensure it is functioning within specifications
5. If necessary, test the ECM for proper operation

How to fix DTC P1400 on Lexus

1. Replace the sub-throttle position sensor if it is found to be faulty
2. Repair or replace any damaged wiring or connectors in the sensor circuit
3. If the ECM is determined to be the issue, it may need to be reprogrammed or replaced
4. Clear the fault code and test drive the vehicle to ensure the issue has been resolved

How to erase DTC P1400 on Lexus

1. Use an OBD-II scanner to clear the fault code from the ECM
2. Alternatively, disconnect the vehicle’s battery for a few minutes to reset the ECM and clear the code
3. After clearing the code, monitor the vehicle for any recurrence of the fault code

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