Shift Interlock System: Diagnosis Chevrolet Tahoe III

DIAGNOSTIC CODE INDEX

DIAGNOSTIC CODE INDEX

Diagnostic Instructions

1. Perform the «Diagnostic System Check - Vehicle»(ref-364486-S08087544882010063000000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-364486-S25727745392010063000000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-364486-S17107648382010063000000) provides an overview of each diagnostic category.

Diagnostic Fault Information

Conditions for Running the DTC

1. The ignition switch is in the ON position.
2. The brake pedal is pressed.
3. The transmission is in the PARK position.

Conditions for Setting the DTC

The DTC sets if there is a short to ground 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.

Conditions for Clearing the DTC

1. A current DTC B2705 will clear when the malfunction is no longer present and the ignition switch is cycled.
2. A history DTC will clear after 100 ignition cycles with no current DTC active during the 100 ignition cycles.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the shift lock control solenoid.
2. Ignition OFF, test for less than 5.0 ohm between the ground circuit terminal B and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
3. Install a test lamp between the ground circuit terminal B and the control circuit terminal A.
4. Ignition ON, command the scan tool BCM Shift Lock Solenoid output control ON and OFF. The test lamp should turn ON and OFF as commanded. If the test lamp is always ON, test the control circuit for short to voltage. If the circuit tests normal, replace the BCM. If the test lamp is always OFF, test the control circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
5. If the circuit tests normal, replace the transmission control.

Visual/Physical Inspection

1. Inspect for aftermarket devices which could affect the operation of the automatic transmission shift lock control. Refer to «Checking Aftermarket Accessories»(ref-364488-S07680217832010063000000) .
2. Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

Symptom List

Refer to a symptom diagnostic procedure in order to diagnose the symptom

Transmission Control Lever Malfunction

1. Perform the «Diagnostic System Check - Vehicle»(ref-364486-S08087544882010063000000) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(ref-364486-S25727745392010063000000) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(ref-364486-S17107648382010063000000) provides an overview of each diagnostic category.

1. Ignition OFF, disconnect the harness connector at the shift lock control solenoid.
2. Ignition OFF, test for less than 5.0 ohm between the ground circuit terminal B and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
3. Install a test lamp between the ground circuit terminal B and the control circuit terminal A.
4. Ignition ON, command the scan tool BCM Shift Lock Solenoid output control ON and OFF. The test lamp should turn ON and OFF as commanded. If the test lamp is always ON, test the control circuit for short to voltage. If the circuit tests normal, replace the BCM. If the test lamp is always OFF, test the control circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
5. If the circuit tests normal, replace the transmission control.