P1128 – Lexus DTC

Lexus DTC P1128 – Throttle Control Motor Lock Malfunction

DTC P1128 meaning on Lexus

DTC P1128 for Lexus indicates a Throttle Control Motor Lock Malfunction. This fault code is triggered when the Engine Control Module (ECM) detects an issue with the throttle control motor’s locking mechanism.

Lexus DTC P1128 symptoms

• Check Engine Light (CEL) illuminated on the dashboard
• Reduced engine power or acceleration
• Difficulty maintaining a steady idle
• Possible stalling or rough idling

Lexus DTC P1128 causes

• Throttle control motor failure
• Wiring or connector issues in the throttle control circuit
• ECM malfunction
• Mechanical obstruction in the throttle body

Lexus DTC P1128 seriousness

The DTC P1128 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 P1128 on Lexus

1. Use a diagnostic scanner to retrieve the trouble codes stored in the ECM
2. Inspect the throttle control motor and its wiring for any visible damage or loose connections
3. Check the throttle body for any obstructions or sticking components
4. Perform a thorough inspection of the ECM and related circuits

How to fix DTC P1128 on Lexus

1. Replace the throttle control motor if it is found to be faulty
2. Repair or replace any damaged wiring or connectors in the throttle control circuit
3. Clean the throttle body to ensure smooth operation
4. If necessary, replace the ECM with a new unit

How to erase DTC P1128 on Lexus

1. Use a diagnostic scanner to clear the trouble codes stored in the ECM
2. After making the necessary repairs, drive the vehicle to allow the ECM to perform a self-check
3. If the issue has been resolved, the Check Engine Light should turn off automatically

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