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 Descriptors
DTC B2705 02: Gearshift Unlock Circuit Short to GroundDTC B2705 05: Gearshift Unlock Circuit Short to Battery or Open
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Shift Lock Control Solenoid Voltage Supply Circuit | -- | B2705 05 | B2705 05 | -- |
Shift Lock Control Solenoid Ground Circuit | B2705 02 | -- | -- | -- |
Circuit/System Description
The body control module (BCM) controls the automatic transmission shift lock control solenoid by providing a battery positive voltage to the solenoid. The BCM utilizes a smart driver to control the voltage supply circuit to the automatic transmission shift lock control solenoid. The smart driver monitors the voltage and current flow of the control circuit.
Conditions for Running the DTC
| • | The ignition switch is in the ON position. |
| • | The brake pedal is pressed. |
| • | The transmission is in the PARK position. |
Conditions for Setting the DTC
B2705 02
Sets if there is a short to ground in the automatic transmission shift lock control solenoid control circuit.
B2705 05
Sets if there is an open or short to voltage in the automatic transmission shift lock control solenoid control circuit.
Action Taken When the DTC Sets
| • | The BCM will not attempt to enable the voltage supply circuit of the automatic transmission shift lock control solenoid until the next key cycle. |
| • | The BCM stores DTC B2705 in memory. |
Conditions for Clearing the DTC
| • | A current DTC B2705 will clear when the malfunction is no longer present and the ignition switch is cycled. |
| • | All BCM history codes will clear after 100 ignition cycles with no current codes active during the 100 ignition cycles. |
Reference Information
Schematic Reference
Connector End View Reference
Shift Lock Control Connector End Views
Description and Operation
Automatic Transmission Shift Lock Control Description and Operation
Electrical Information Reference
Scan Tool Reference
Circuit/System Verification
Clear the DTC and verify that the brake pedal has to be pressed so that the transmission can be shifted out of the PARK position.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the shift lock control solenoid.
- Ignition OFF, test for less than 1.0 ohm of resistance between the ground circuit terminal 3 and ground.
- Ignition ON and the engine OFF, command the Brake To Shift Control output control ON and OFF. The automatic transmission shift lock control solenoid should turn ON and OFF and allow the transmission to be shifted out of the PARK position.
- Ignition ON and the engine OFF, connect a test lamp between the shift lock control solenoid ground circuit at the connector of the shift lock control solenoid and battery positive voltage. With the brake pedal applied, the test lamp should illuminate.
| ⇒ | If greater than the specified range, test the ground circuit for an open. If the circuit tests normal, replace the shift lock control solenoid. |
| ⇒ | If unable to shift out of PARK, test for an open or short to ground in the control circuit. |
| ⇒ | If test lamp does not illuminate, replace the shift lock control solenoid. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
