CODE 31 - Wastegate Solenoid Circuit Error
Trouble Code 31 indicates that the Wastegate Solenoid may not be functioning correctly. The wastegate solenoid is controlled by a Pulse Width Modulated (PWM) signal from the ECM. The ECM controls turbo boost by varying the PWM waveform (duty cycle) to the wastegate. The wastegate responds by bleeding off exhaust pressure upstream of the turbine, thus controlling boost pressure.
The conditions for setting this code are:
Typical causes for this code include:
1) Poor or corroded connections between the ECM and the wastegate solenoid
2) Open or shorted solenoid
3) Defective, sticking or maladjusted wastegate linkage
4) Defective ECM
Ensure correct operation of other engine subsystems, including but not limited to the TPS and MAF sensors and check the wastegate actuation hardware.