Fault code P1517 – a step-by-step guide to diagnosing and fixing it

Error code P1517 is displayed and the check engine light is on - what does this mean?

The DTC P1517 is recognized by the OBD system when there is a problem with the throttle control module or the electronic throttle control. This manufacturer-specific error code mainly affects the engine management and the air supply, although different definitions are possible for different manufacturers such as BMW, Mercedes-Benz or Audi.

What causes can this error code have?

• Defective throttle valve control unit
• Damaged wiring to the throttle sensor
• Dirty or jammed throttle valve
• Faulty throttle position sensors
• Defective plug connections on the throttle body
• Software error in the engine control unit
• Mechanical damage to the throttle valve unit
• Interruption in the power supply

What symptoms occur in parallel with fault code P1517?

• Irregular idling: The engine runs irregularly or stutters when idling
• Reduced engine power: Noticeable loss of power when accelerating
• Starting problems: Difficulty starting the engine
• Jerky engine: Uneven engine running at different engine speeds
• Increased fuel consumption: Significantly higher consumption than usual
• Emergency running program: The vehicle switches to emergency running mode
• Check engine light: Permanent illumination of the warning light

How can the problem with fault code P1517 be rectified?

• Repairing fault code P1517 requires a systematic approach to identify the exact cause.
• Carry out throttle valve cleaning: Remove the throttle body and clean it thoroughly with special throttle body cleaner to remove debris and dirt that can cause malfunctions.
• Check wiring and plug connections: Check all cable connections to the throttle valve module for damage, corrosion or loose contacts and repair or replace defective components.
• Replace throttle valve control unit: Replace the defective control unit with a new or reconditioned replacement part and then carry out reprogramming or adjustment.
• Replace complete throttle body: Replace the entire throttle body assembly, including sensors and actuators, if multiple components are defective or repair is not economical.
• Perform software update: Update the engine control unit software to the latest version to correct known software errors that can cause trouble code P1517.
• Basic setting of the throttle valve: Carry out a basic setting or adjustment of the throttle valve position with a diagnostic device to ensure correct function after repairs.