2010 Cadillac CTS Sedan AWD V6-3.6L Page 1704
* TP is 8 percent or greater.
* Engine torque is 75 Nm (55 lb ft) or greater.
* Vehicle speed is 10 km/h (6 mph) or greater.
Conditions for Setting the DTC
P0850 or P0851
The ECM detects the Park/Neutral switch signal equals 0 volts, Low, when the IMS reports a Drive range.
P0852
The ECM detects the Park/Neutral switch signal equals 12 volts, High, when the IMS reports a Park/Neutral range.
Action Taken When the DTC Sets
* DTCs P0850, P0851, and P0852 are Type C DTCs.
* The ECM uses IMS Range for engine start-up.
Conditions for Clearing the DTC
DTCs P0850, P0851, and P0852 are Type C DTCs.
Reference Information
Schematic Reference
* Automatic Transmission Controls Schematics (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Diagrams)
* Engine Controls Schematics (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)
Connector End View Reference
* Component Connector End Views (See: Diagrams/Connector Views)
* Inline Harness Connector End Views (See: Power and Ground Distribution/Multiple Junction Connector/Diagrams)
Description and Operation
* Transmission General Description (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Description and
Operation/Transmission General Description)
* Transmission Component and System Description (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Description and
Operation/Transmission Component and System Description)
* Electronic Component Description (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Description and
Operation/Electronic Component Description)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit
Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Wiring Repairs/Wiring Repairs)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code
(DTC) Type Definitions)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
Special Tools
DT-47825-10 - Jumper Harness
For equivalent regional tools, refer to Special Tools (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Tools and Equipment).
Circuit/System Verification
1. If there are any other transmission DTCs set, diagnose those DTCs first. Refer to Diagnostic Trouble Code (DTC) List - Vehicle (See:
Diagnostic Trouble Code Descriptions/Diagnostic Trouble Code (DTC) List - Vehicle).
2. Ignition ON, observe the scan tool ECM Park/Neutral switch parameter while moving the gear shift lever from Park and through all ranges.
The parameter should display Park/Neutral when in Park or Neutral and In-Gear when in Reverse or Drive.
