GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • 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.

DTC Descriptor

DTC P0706: Park/Neutral Position Switch Circuit

DTC P0707: Park/Neutral Position Switch Circuit Low Voltage

DTC P0708: Park/Neutral Position Switch Circuit High Voltage

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Park/Neutral Signal

P0706, P0707

P0706, P0708

P0706, P0708

--

Typical Scan Tool Data

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Operating Conditions: Engine running, normal operating temperature

Parameter Normal Range: 12 Volts = In-Gear, 0 Volts = Park/Neutral

Park/Neutral Signal

Park/Neutral

In-Gear

In-Gear

Circuit/System Description

Shift position switch function is installed as one part of transmission control module (TCM). The position switch consists of 2 switches, whose values are running in the opposite direction. automatic transmission shift range is calculated by TCM reading output voltage from gear lever position sensor installed in TCM itself.

Conditions for Running the DTC

    • Ignition voltage is between 6-15.5 V.
    • TCM is not in service mode.

Conditions for Setting the DTC

P0706

Sum of two position sensor voltage has deviation over 0.29 V from standard value 5 V.

P0707

Voltage on position switch 1 and position switch 2 is less than 0.127 V for 100 ms continuously after 2 consecutive times.

P0708

Voltage on position switch 1 and position switch 2 is more than 4.87 V for 100 ms continuously after 2 consecutive times.

Action Taken When the DTC Sets

    • DTCs P0706, P0707, and P0708 are Type A DTCs.
    • The TCM freezes transmission adaptive functions.
    • If output speed sensor is 0 RPM, Range is D, 2nd gear is hold and service mode will be set.
    • The engine start is locked after engine has stopped.

Conditions for Clearing the DTC

    • DTCs P0706, P0707, and P0708 are Type A DTCs.
    • Voltage of two selector position sensor are within 0.127-4.87 V and sum of two position sensor voltage has deviation within 0.29 V from standard value 5 V.

Reference Information

Schematic Reference

Automatic Transmission Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Transmission Component and System Description

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

Control Module References for scan tool information

Circuit/System Verification

  1. If there are any other transmission DTCs set, diagnose those DTCs first. Refer to Diagnostic Trouble Code (DTC) List - Vehicle.
  2. Note: It is especially important to closely observe the Park and Neutral to Drive transitional positions while moving the shift lever and observing for possible misalignment or slack in the shifter mechanism.

  3. Ignition ON, observe the scan tool transmission range switch parameter while slowly moving the gear shift lever from Park and through all ranges. Verify the gear shift lever position matches the scan tool parameter.
  4. If not within the specified value, refer to range selector lever cable adjustment Range Selector Lever Cable Adjustment and Transmission Adaptive Functions.
  5. Ignition ON, observe the scan tool transmission range switch parameter while slowly moving the gear shift lever from Park and through all ranges. Verify the gear shift lever position matches the scan tool parameter.
  6. If not within the specified value, replace the K71 Transmission Control Module (TCM).
  7. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
  8. If the DTC resets, replace the K71 Transmission Control Module (TCM).

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    • Control valve body, refer to Control Valve Body Replacement for replacement.
    • TCM, refer to Control Module References for replacement, setup and programming.