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Q: What does the reduced engine power Warning Light mean?

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What does the reduced engine power Warning Light mean?

The purpose of the “Reduced Engine Power” Warning Light is to alert drivers when/if there is a serious problem with the transmission and/or one or more of the engine system components. When a fault/error in the transmission or engine triggers the Reduced Engine Power Warning Light, the vehicle will experience an extreme loss of power and performance and vehicles may not be able to exceed speeds greater than 20 miles per hour. The Powertrain Control Module (PCM) will store one or more diagnostic trouble codes for the purpose of diagnosing the fault/error in the system.

An issue or malfunction in the throttle control system is most common when the Reduced Engine Power Warning Light illuminates in the dashboard. However, there are other components and systems that will trigger the Reduced Engine Power Warning Light, in the event of a problem.

  • Defective throttle position (TP) sensor
  • Defective oxygen sensor
  • Defective accelerator pedal position (APP) sensor
  • Loose or damaged wiring
  • Defective throttle body
  • Defective powertrain control module (PCM)
  • Any fault/error that will affect drivability function
  • Any fault/error that will affect vehicle performance
  • A fault/error in the emissions system
  • A fault/error in the throttle control system
  • A fault/error in the transmission system

The Reduced Engine Power Warning Light is considered extremely serious because of the immediate and severe drivability problems that will be present until the engine or transmission fault/error is repaired. If the Reduced Engine Power Warning Light is ON in your vehicle, contact a mechanic, such as one from YourMechanic, to have it diagnosed and repaired.

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