P071D
DTC P071D
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptor
DTC P071D
- Transmission Sport Mode Switch Circuit
Diagnostic Fault Information
Circuit/System Description
The Body Control Module (BCM) supplies a signal circuit to the sport mode switch. When the sport mode switch is momentarily pressed, the signal circuit is connected to ground. The BCM detects the change in voltage and initiates sport mode and sends a GMLAN message to the transmission control module (TCM) indicating the status of sport mode. The status of the sport mode switch is also sent as a GMLAN message. When sport mode is active, the TCM modifies the transmission shift points.
Conditions for Running the DTC
* Engine speed is 500-7,500 RPM for 5 s.
* Ignition voltage is between 9-18 V.
* DTC runs continuously when the above conditions are met.
Conditions for Setting the DTC
TCM detects that the sport mode switch has been continuously activated for 10 min.
Action Taken When the DTC Sets
* P071D is a type C DTC.
* TCM inhibits the sport mode shift pattern.
* TCM inhibits Tap Up/Down function.
* TCM inhibits manual shifting of forward gears.
Conditions for Clearing the DTC
P071D is a Type C DTC.
Diagnostic Aids
Diagnose all communication and body DTCs first.
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics 6T40/6T50 (MHH, MHK) - Automatic Transmission
Connector End View Reference
* Component Connector End Views Sunshade - Left
* Inline Harness Connector End Views X100
Description and Operation
* Electronic Component Description Electronic Component Description
* Transmission General Description Transmission General Description
* Transmission Component and System Description Transmission Component and System Description
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Control Module References for scan tool information.
Circuit/System Verification
1. Ignition ON.
2. Verify the scan tool Transmission Sport Mode parameter changes between Active and Inactive each time the sport mode switch is depressed and released.
• If Inactive or Active is not displayed
Refer to Circuit/System Testing.
• If Inactive and Active are displayed
3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
4. Verify the DTC does not set.
• If the DTC sets
Refer to Circuit/System Testing.
• If the DTC does not set
5. All OK.
Circuit/System Testing
Note: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.
1. Ignition OFF, disconnect the harness connector at the S48D Multifunction Switch 2 - Instrument Panel.
2. Test for less than 10 ohms between the vehicle harness connector ground circuit terminal 2 and ground.
• If 10 ohms or greater
1. Ignition OFF.
2. Test for less than 2 ohms in the ground circuit, end to end.
• If 2 ohms or greater, repair the open/high resistance in the ground circuit.
• If less than 2 ohms, repair the open/high resistance in the ground connection.
• If less than 10 ohms
3. Ignition ON.
4. Test for greater than 11 V between the vehicle harness connector signal circuit terminal 5 and ground.
• If less than 11 V
1. Ignition OFF, remove the harness connector at the BCM.
2. Test for infinite resistance between the signal circuit and ground.
• If less than infinite resistance, repair the short to ground in the circuit.
• If infinite resistance.
3. Test for less than 2 ohms in the signal circuit, end to end.
• If 2 ohms or greater, repair the open/high resistance in the 5 V reference circuit.
• If less than 2 ohms, replace the K9 Body Control Module.
• If greater than 11 V
5. Ignition OFF, install a 3 amp fused jumper between vehicle harness connector signal circuit terminal 5 and ground, ignition ON.
6. Verify the scan tool Transmission Sport Mode parameter changes between Inactive and Active each time the jumper wire is connected to ground and then removed.
• If Active or Inactive is not displayed
Replace the K9 Body Control Module.
• If Active and Inactive are displayed
7. Replace the S48D Multifunction Switch 2 - Instrument Panel.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Instrument Panel Multifunction Switch Replacement Service and Repair
* Control Module References Control Module References for Control Solenoid Valve Assembly or Engine Control Module replacement, programming and setup.