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For 1990-2009 cars only
Makes 🢒 Buick 🢒 2004 🢒 Regal 🢒 Transmission/Transaxle 🢒 Shift Lock Control 🢒 Shift Lever Does Not Move with Brake Pedal Depressed

Shift Lever Does Not Move with Brake Pedal Depressed Century

Step

Action

Yes

No

Schematic Reference: Shift Lock Control Schematics

Connector End View Reference: Shift Lock Control Connector End Views or Body Control System Connector End Views in Body Control System

DEFINITION: Transmission shift lever will not move out of the PARK position with the ignition ON and the brake pedal pressed.

1

Did you perform the Diagnostic System Check - Automatic Transmission Shift Lock Control tests and all the necessary inspections?

Go to Step 2

Go to Diagnostic System Check - Automatic Transmission Shift Lock Control

2
  1. Turn ON the ignition, with the engine OFF.
  2. Press and hold the brake pedal.
  3. Attempt to move the shift lever out of the PARK position.

Does the shift lever move out of the PARK position?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3
  1. Turn OFF the ignition.
  2. Disconnect the automatic transmission shift lock control switch.
  3. Turn ON the ignition, with the engine OFF.
  4. Press and hold the brake pedal.
  5. Attempt to move the transmission shift lever out of the PARK position.

Does the transmission shift lever move out of the PARK position?

Go to Step 5

Go to Step 4

4
  1. Turn OFF the ignition.
  2. Disconnect the automatic transmission shift lock control solenoid.
  3. Turn ON the ignition, with the engine OFF.
  4. Press and hold the brake pedal.
  5. Attempt to move the transmission shift lever out of the PARK position.

Does the transmission shift lever move out of the PARK position?

Go to Step 7

Go to Step 6

5
  1. Inspect for proper adjustment of the automatic transmission shift lock control switch. Refer to Stop Lamp Switch Adjustment in Lighting Systems.
  2. Inspect for poor connections at the automatic transmission shift lock control switch. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 8

6

Inspect for poor connections at the automatic transmission shift lock control solenoid. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 10

Go to Step 9

7

Repair the short to battery positive voltage in the automatic transmission shift control solenoid voltage supply circuit. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 10

--

8

Replace the automatic transmission shift lock control switch. Refer to Stop Lamp Switch Replacement in Lighting Systems.

Did you complete the repair?

Go to Step 10

--

9

Replace the automatic transmission shift lock control solenoid. Refer to Automatic Transmission Shift Lock Actuator Replacement .

Did you complete the replacement?

Go to Step 10

--

10

Operate the system in order to verify the repair.

Did you find and correct the condition?

System OK

Go to Step 2

Shift Lever Does Not Move with Brake Pedal Depressed Regal

Step

Action

Yes

No

Schematic Reference: Shift Lock Control Schematics

Connector End View Reference: Shift Lock Control Connector End Views or Body Control System Connector End Views in Body Control System

DEFINITION: Transmission shift lever will not move out of the PARK position with the ignition ON and the brake pedal pressed.

1

Did you perform the Diagnostic System Check - Automatic Transmission Shift Lock Control tests and all the necessary inspections?

Go to Step 2

Go to Diagnostic System Check - Automatic Transmission Shift Lock Control

2
  1. Turn ON the ignition, with the engine OFF.
  2. Press and hold the brake pedal.
  3. Attempt to move the shift lever out of the PARK position.

Does the shift lever move out of the PARK position?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3
  1. Turn OFF the ignition.
  2. Disconnect the automatic transmission shift lock control switch.
  3. Turn ON the ignition, with the engine OFF.
  4. Press and hold the brake pedal.
  5. Attempt to move the transmission shift lever out of the PARK position.

Does the transmission shift lever move out of the PARK position?

Go to Step 12

Go to Step 4

4
  1. Turn OFF the ignition.
  2. Disconnect the automatic transmission shift lock control solenoid.
  3. Turn ON the ignition, with the engine OFF.
  4. Press and hold the brake pedal.
  5. Attempt to move the transmission shift lever out of the PARK position.

Does the transmission shift lever move out of the PARK position?

Go to Step 16

Go to Step 5

5
  1. Turn OFF the ignition.
  2. Connect a test lamp between the park lock control solenoid voltage supply circuit and a good ground.
  3. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

Go to Step 6

Go to Step 17

6
  1. Turn OFF the ignition.
  2. Connect a test lamp between the park lock control solenoid voltage supply circuit and the park lock solenoid controlled ground circuit at the connector of the park lock control solenoid.
  3. Install a scan tool.
  4. Turn ON the ignition, with the engine OFF.
  5. With a scan tool, command the brake to shift relay output control ON and OFF several times while observing the test lamp.

Does the test lamp turn ON and OFF with each command?

Go to Step 13

Go to Step 7

7
  1. Turn OFF the ignition.
  2. Disconnect the brake to shift relay.
  3. Connect a test lamp between the voltage supply circuit of the brake to shift relay and a good ground.
  4. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

Go to Step 8

Go to Step 18

8
  1. Turn OFF the ignition.
  2. Connect a test lamp between the brake to shift relay voltage supply circuit and the brake to shift relay ground circuit at the connector of the brake to shift relay.
  3. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

Go to Step 9

Go to Step 19

9
  1. Turn OFF the ignition.
  2. Connect a test lamp between the brake to shift relay voltage supply circuit and the brake to shift relay control circuit at the connector of the brake to shift relay.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, command the brake to shift relay ON and OFF in the body control module output control data list.

Does the test lamp turn ON and OFF with each command?

Go to Step 10

Go to Step 11

10
  1. Turn OFF the ignition
  2. Connected a 10 amp fused jumper between the shift lock solenoid control circuit and the brake to shift relay ground circuit at the brake to shift relay connector.
  3. Connect a test lamp between the voltage supply circuit and the control circuit of the park lock control solenoid at the park lock control solenoid connector.
  4. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

Go to Step 14

Go to Step 20

11

Test the brake to shift relay control circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 25

Go to Step 15

12
  1. Inspect for proper adjustment of the automatic transmission shift lock control switch. Refer to Stop Lamp Switch Adjustment in Lighting Systems.
  2. Inspect for poor connections at the harness connector of the automatic transmission shift lock control switch. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 25

Go to Step 21

13

Inspect for poor connections at the harness connector of the park lock control solenoid. Refer to Underhood Electrical Center or Junction Block Replacement and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 25

Go to Step 22

14

Inspect for poor connections at the harness connector of the brake to shift relay. Refer to Underhood Electrical Center or Junction Block Replacement and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 25

Go to Step 23

15

Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Underhood Electrical Center or Junction Block Replacement and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 25

Go to Step 24

16

Repair the short to battery positive voltage in the automatic transmission shift control solenoid voltage supply circuit. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 25

--

17

Repair the open or short to ground in the park lock control solenoid voltage supply circuit. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 25

--

18

Repair the open or short to ground in the brake to shift relay voltage supply circuit. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 25

--

19

Repair the open in the brake to shift relay ground circuit. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 25

--

20

Repair the open or short to ground in the controlled ground circuit of the park lock control solenoid. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 25

--

21

Replace the automatic transmission shift lock control switch. Refer to Stop Lamp Switch Replacement in Lighting Systems.

Did you complete the repair?

Go to Step 25

--

22

Replace the automatic transmission shift lock control solenoid. Refer to Automatic Transmission Shift Lock Actuator Replacement .

Did you complete the replacement?

Go to Step 25

--

23

Replace the brake to shift relay. Refer to Relay Replacement in Wiring Systems.

Did you complete the repair?

Go to Step 25

--

24

Replace the body control module (BCM). Refer to Body Control Module Replacement in Body Control System.

Did you complete the repair?

Go to Step 25

--

25

Operate the system in order to verify the repair.

Did you find and correct the condition?

System OK

Go to Step 2