Diagnosing Jeep Diagnostic Codes

Diagnosing Diagnostic Codes

The codes being diagnosed in this article are P0507, P0871 and P0934.

Courtesy of Transmission Digest

The codes being diagnosed in this article are:

  • P0507: Idle speed performance higher than expected
  • P0871: OD pressure switch rationality
  • P0934: Line pressure sensor circuit low

A 2006 Jeep Commander using a 545RFE transmission arrived at our shop from an independent muffler and general repair facility with three codes: P0507, P0871 and P0934. The codes are for Idle Speed, OD Pressure Switch and Line Pressure Sensor Circuit fault, all in that order.
The history known of the vehicle up to this point was that the transmission had failed, exhibiting a symptom of a no-move condition. The independent repair shop chose to install a rebuilt transmission and torque converter before the vehicle arrived at our shop. After a fluid check and scanning for codes, we took the vehicle on a short test drive. During this road test, we noted that drive engagement was a little lazy along with a tie-up going into the first 2-3 shift which immediately initiated limp-in mode, setting code P0871 only. After erasing this code, a quick learn was performed, but this resulted in no change in the drivability issues of the vehicle along with the return of P0871.

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