Document ID: 1922532

Note: The following steps must be completed before using the symptom tables.

Perform the Diagnostic System Check - Vehicle before using the Symptom Tables in order to verify that all of the following are true:

There are no DTCs set.
The control modules can communicate via the serial data link.

Review the system operation in order to familiarize yourself with the system functions. Refer to Automatic Transmission Shift Lock Control Description and Operation.

Visual/Physical Inspection

Inspect for aftermarket devices which could affect the operation of the automatic transmission shift lock control.
Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections

Symptom List

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

Transmission Control Lever Malfunction

Document ID: 2220788

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.

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
Control	B270A 02	B270A 04	B270A 01	—
Ground	—	B270A 04	—	—

Circuit/System Description

The body control module (BCM) controls the transmission shift lock control solenoid actuator by providing a battery positive voltage to the solenoid when the brake pedal is applied. The BCM monitors the voltage and current flow of the control circuit.

Reference Information

Schematic Reference

Shift Lock Control Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Automatic Transmission Shift Lock Control Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Ignition ON.
Verify the scan tool Brake Transmission Shift Interlock Solenoid Actuator Command parameter changes from Inactive to Active when the brake pedal is applied.

If the parameter does not change
Refer to Stop Lamps Malfunction

If the parameter changes

Verify the S3 Transmission Shift Lever moves out of the PARK position when the brake pedal is applied.

If the S3 Transmission Shift Lever does not move out of the PARK position
Refer to Circuit/System Testing.

If the S3 Transmission Shift Lever does move out of the PARK position
All OK.

Circuit/System Testing

Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the S3 Transmission Shift Lever. It may take up to 2 min for all vehicle systems to power down.
Test for less than 10 Ω between the ground circuit terminal 7 and ground.

If 10 Ω or greater

Ignition OFF.
Test for less than 2 Ω in the ground circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.
If less than 2 Ω, repair the open/high resistance in the ground connection.

If less than 10 Ω

Ignition ON, connect a test lamp between the control circuit terminal 1 and the ground circuit terminal 7.
Verify the test lamp turns ON and OFF when commanding the Brake Transmission Shift Interlock Solenoid Actuator ON and OFF with a scan tool.

If the test lamp is always OFF

Ignition OFF, disconnect the harness connector at the K9 Body Control Module.
Test for infinite resistance between the control circuit and ground.

If less than infinite resistance, repair the short to ground on the circuit.

If infinite resistance

Test for less than 2 Ω in the control circuit end to end.

If 2 Ω or greater, repair the open/high resistance in the circuit.

If less than 2 Ω

Ignition ON.
Verify a test lamp illuminates between each B+ and ignition circuit terminal at the control module harness connector.

If the test lamp does not illuminate, repair the circuit or fuse as necessary.

If the test lamp illuminates at each B+ and ignition circuit, replace the K9 Body Control Module.

If the test lamp is always ON

Ignition OFF, disconnect the harness connector at the K9 Body Control Module, ignition ON.
Test for less than 1 V between the control circuit and ground.

If 1 V or greater, repair the short to voltage on the circuit.
If less than 1 V, replace the K9 Body Control Module.

If the test lamp turns ON and OFF

Test or replace the S3 Transmission Shift Lever.

Component Testing

Dynamic Test

Install a 10 A fused jumper wire between the control terminal 1 and 12 V. Momentarily install a jumper wire between the ground terminal 7 and ground.
Verify the M7 Transmission Shift Lock Control Solenoid Actuator turns on & off/clicks, etc.

If the M7 Transmission Shift Lock Control Solenoid Actuator does not turn on & off/clicks, etc.
Replace the S3 Transmission Shift Lever.

If the M7 Transmission Shift Lock Control Solenoid Actuator does turn on & off/clicks, etc.

All OK

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Transmission Control Replacement
Control Module References for BCM replacement, programming, and setup

Shift Interlock

Related components