P0638 MERCEDES-BENZ – Throttle Actuator Control Range/Performance Bank 1

 

P0638: DIY Repairing Video Tutorial

https://youtu.be/a066l-jZS5k

Check out nonda Auto DIY Center for more engine error code repairing videos.
https://www.youtube.com/playlist?list=PL-Lyko0O0oxHe1AGvzwAz-wokJPXAtW97

 

P0638 MERCEDES-BENZ Possible Symptoms

  Engine Light ON (or Service Engine Soon Warning Light)  

P0638 MERCEDES-BENZ Possible Causes

  Faulty Accelerator Pedal Position Sensor,Accelerator Pedal Position Sensor harness is open or shorted,Accelerator Pedal Position Sensor circuit poor electrical connection,Faulty Throttle Positioner Motor  

P0638 MERCEDES-BENZ Description

  This fault code is stored in the engine control module when a fault is detected with the throttle positioner motor. The ECM monitors the current flow through the motor and if the current flow is exceeds a predetermined limit this fault code is logged. The ECM uses a comparator circuit to monitor the current flow. A mechanical detect within the throttle valve assembly can effect current flow. Mechanical condition of the throttle valve assembly should be investigated before any electrical fault finding procedure.