Conditions For Setting DTC

NOTE: This DTC may set if the generator L-terminal input is low with engine speed between idle and 1000 RPM. The time to set the DTC varies up to one minute.

DTC P1637 will set if generator L-terminal input voltage at the ECM is less than 4 volts when the condition exists for longer than 3 seconds and engine speed is greater than 1000 RPM.

DTC P1637 diagnostic runs continuously with the engine running. DTC P1637 is a type "D" DTC.