P2138 Accelerator Position Sensor (G79)/(G185)

P2138 accelerator position sensor (G79) /(G185) is set in the engine control module. when the engine control module receive wrong signal coming out from accelerator paddle. there are two strip inside the accelerator paddle for accelerating one strip is work at 50% of accelerator the other work on the another 50% of accelerator. if any one of them will not work P2138 fault code will set inside the engine control module.

this fault code will not accelerate car engine and illuminate the heater and engine light on the cluster meter. this fault code can also store in engine control module because of a bad throttle body. malfunction in the throttle body also create this fault code. As accelerator pedal and throttle body connected with each other. Throttle body open and close by pressing or depressing the accelerator paddle.

How risky it is to drive with fault code P2138 :

Driving with fault code P2138 cab be risky as this fault code is related to the to problem of powering up the engine. in any case if this problem occurs at high speed it can be very dangerous for the driver as well as passenger.

Cause of P2138 accelerator position sensor (G79) /(G185) :

  • faulty accelerator paddle.
  • faulty throttle body.
  • damage wiring harness of accelerator pedal or throttle body.
  • faulty engine control module.

symptoms :

  • engine will not accelerate.
  • also heater light will illuminate on the cluster meter.
  • engine will not power up.
  • mostly it happen at high speed not on low speed.

Solution of P2138 P2138 accelerator position sensor (G79) /(G185) :

  • replace faulty accelerator paddle position sensor.
  • replace faulty throttle body controller.
  • and also repair or replace engine control module.
  • repair damage and corroded wiring harness.

How to diagnose fault code P2138 :

  • mechanic should start diagnosing fault code by scanning the fault code with the help of scan tool. check the status of fault code if possible then try clear the fault and take a little test drive until the fault code re-appear.
  • with the help of scan tool check the reading of accelerator paddle and throttle body also check the reference voltage of them. rectify the faulty sensor or actuator between accelerator paddle and throttle body. then go to check the wiring harness of accelerator paddle and throttle body for the damage of wire.
  • if the wiring harness of the accelerator paddle and throttle body is good. then check throttle body from inside for the deposition of carbon.
  • most of the time faulty throttle body create this fault code to store in engine control module. but in some cases accelerator paddle create this fault code. both of the them can be faulty at the same time if any short circuit take place between them.

Special Note For P2138 :

Fault code P2138 store in engine control module. because of a faulty accelerator paddle position sensor or faulty throttle body . to solve this problem replace faulty accelerator paddle position sensor or throttle body . if after replacing the accelerator paddle the fault code is still present, after this replace faulty throttle body than can solve the problem. then check the engine control module and repair it if there is problem inside the engine control module sometime ECU suspect faulty.

Leave a Reply