P1129 – Lexus DTC

Lexus DTC P1129 – Electronic Throttle Control System

DTC P1129 meaning on Lexus

The DTC P1129 on a Lexus refers to an issue with the Electronic Throttle Control System. This code indicates that there is a malfunction in the system related to the throttle position sensor.

Lexus DTC P1129 symptoms

Common symptoms of DTC P1129 on a Lexus may include:

• Check Engine Light illuminated on the dashboard
• Reduced engine power or acceleration
• Difficulty maintaining a steady idle

Lexus DTC P1129 causes

The potential causes of DTC P1129 on a Lexus can include:

• Faulty throttle position sensor
• Issues with the throttle body
• Wiring or connector problems in the throttle control circuit

Lexus DTC P1129 seriousness

DTC P1129 should be addressed promptly as it can lead to drivability issues and potentially unsafe driving conditions. Ignoring this code may result in further damage to the vehicle’s engine or drivetrain components.

How to diagnose DTC P1129 on Lexus

Diagnosing DTC P1129 on a Lexus typically involves:

1. Using a diagnostic scanner to retrieve the trouble codes
2. Inspecting the throttle position sensor and related components for any visible damage
3. Testing the throttle position sensor’s voltage and resistance

How to fix DTC P1129 on Lexus

To fix DTC P1129 on a Lexus, you may need to:

1. Replace the faulty throttle position sensor
2. Clean or replace the throttle body if necessary
3. Repair any damaged wiring or connectors in the throttle control circuit

How to erase DTC P1129 on Lexus

To erase DTC P1129 on a Lexus, you can:

1. Use a diagnostic scanner to clear the trouble codes
2. After fixing the underlying issue, drive the vehicle to allow the system to relearn and verify the repair

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