• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Park/Neutral Signal | P0851 | P0852 | P0852 | -- |
When the transmission is in Park or Neutral, the switch closes. The ECM uses the switch in order to enable starter operation.
• | Ignition voltage is between 11-18 volts. |
• | No VSS faults exist. |
• | No communication faults between TCM and ECM. |
The ECM detects the gear is in park or neutral while the following conditions are met:
• | Vehicle speed is greater than 10 km/h. |
• | Torque command is greater than 60 Nm. |
• | Effective pedal position is greater than 10 %. |
• | Torque converter slip RPM is between -20 RPM and 20 RPM. |
The ECM detects the gear is not in park or neutral while the gear position from TCM is park or neutral.
DTCs P0851 and P0852 are Type C DTCs.
DTCs P0851 and P0852 are Type C DTCs.
Automatic Transmission Controls Schematics
Electronic Component Description
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Control Module References for scan tool information
⇒ | If not the specified value, refer to Range Selector Lever Cable Adjustment. |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
⇒ | If not the specified value, test the park/neutral signal circuit terminal 9 for a short to ground. If the circuit tests normal, replace the ECM. |
⇒ | If not the specified value, test the park/neutral signal circuit for an open/high resistance. If the circuit tests normal, replace the ECM. |
Perform the Diagnostic Repair Verification after completing the repair.
• | Control Module References for ECM replacement, setup, and programming |