GM Service Manual Online
For 1990-2009 cars only

Shift Lever Can Be Moved without Brake Pedal Depressed Pontiac

Step

Action

Yes

No

Schematic Reference: Shift Lock Control Schematics

DEFINITION: Transmission shift lock does not lock in the PARK position with the ignition ON and the brake pedal not press or with the ignition OFF.

1

Did you perform the Symptoms- Automatic Transmission Shift Lock Control tests and necessary inspections?

Go to Step 2

Go to Symptoms - Automatic Transmission Shift Lock Control

2

  1. Turn ON the ignition, with the engine OFF.
  2. Apply the parking brakes and block the wheels.
  3. Attempt to move the shift lever out of the PARK position without pressing the brake pedal.

Does the shift lever move out of the PARK position?

Go to Step 3

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

3

  1. Turn OFF the ignition.
  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 Step 4

Go to Step 5

4

Test for a short to battery positive voltage in the ignition 3 circuit of the park lock solenoid. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 8

5

  1. Connect a test lamp between the automatic transmission shift lock control switch ignition 3 voltage circuit and a good ground.
  2. Turn ON the ignition, with the engine OFF

Does the test lamp illuminate?

Go to Step 6

Go to Step 11

6

  1. Turn OFF the ignition.
  2. Connect a test lamp between the A/T shift lock control solenoid supply voltage circuit at the automatic transmission shift lock control switch and a good ground.
  3. Turn ON the ignition, with the engine OFF.
  4. Press and release the brake pedal several times.

Does the test lamp turn ON and OFF with the brake pedal?

Go to Step 7

Go to Step 9

7

  1. Turn OFF the ignition.
  2. Connect a test lamp between the A/T shift lock control solenoid supply voltage circuit at the automatic transmission shift lock control solenoid and a good ground.
  3. Turn ON the ignition, with the engine OFF.
  4. Press and release the brake pedal several times.

Does the test lamp turn ON and OFF with the brake pedal?

Go to Step 8

Go to Step 10

8

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

Did you find and correct the condition?

Go to Step 14

Go to Step 13

9

  1. Inspect the automatic transmission shift lock control switch for proper adjustment. Refer to Stop Lamp Switch Adjustment in Hydraulic Brakes.
  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 Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 12

10

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

Did you complete the repair?

Go to Step 14

--

11

Repair the open in the automatic transmission shift lock control switch ignition 3 voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 14

--

12

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

Did you complete the replacement?

Go to Step 14

--

13

Replace the automatic shift lock control/park lock solenoids. Refer to Transmission Control Replacement in Automatic Transaxle 4T65-E.

Did you complete the replacement?

Go to Step 14

--

14

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2

Shift Lever Can Be Moved without Brake Pedal Depressed Buick

Step

Action

Yes

No

Schematic Reference: Shift Lock Control Schematics

DEFINITION: Transmission shift lever does not lock in the PARK position with the ignition ON and the brake pedal not pressed.

1

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

Go to Step 2

Go to Symptoms - Automatic Transmission Shift Lock Control

2

  1. Apply the parking brake and block the wheels.
  2. Turn ON the ignition, with the engine OFF.
  3. Attempt to move the shift lever out of the PARK position.

Does the shift lever move out of the PARK position?

Go to Step 3

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

3

  1. Turn OFF the ignition.
  2. Connect a test lamp between the Ignition 1 circuit at the park/neutral position switch and a good ground.
  3. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

Go to Step 4

Go to Step 12

4

  1. Ensure transmission shift lever is in the PARK position.
  2. Connect a test lamp between the park/neutral position switch park signal circuit at the park/neutral position switch and a good ground.

Does the test lamp illuminate?

Go to Step 5

Go to Step 9

5

Connect a test lamp between the park/neutral position switch park signal circuit at the automatic transmission shift lock control switch and a good ground.

Does the test lamp illuminate?

Go to Step 6

Go to Step 13

6

  1. Connect a test lamp between the A/T shift lock control solenoid supply voltage circuit at the automatic transmission shift lock control switch and a good ground.
  2. Press and release the brake pedal several times.

Does the test lamp turn ON and OFF with the brake pedal?

Go to Step 7

Go to Step 10

7

  1. Connect a test lamp between the A/T shift lock control solenoid voltage supply circuit at the automatic transmission shift lock control solenoid and a good ground.
  2. Press the brake pedal.

Does the test lamp illuminate?

Go to Step 8

Go to Step 14

8

Connect a test lamp between the ground circuit at the automatic transmission shift lock control solenoid and battery positive voltage.

Does the test lamp illuminate?

Go to Step 11

Go to Step 15

9

    • Inspect for proper park/neutral position switch adjustment. Refer to Park/Neutral Position Switch Adjustment in Automatic Transaxle- 4T65-E.
    • Inspect for poor connections at the park/neutral position 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 19

Go to Step 16

10

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 19

Go to Step 17

11

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 19

Go to Step 18

12

Repair the open in the ignition 1 power feed circuit. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 19

--

13

Repair the open in the park/neutral position switch park signal circuit. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 19

--

14

Repair the open in the A/T shift 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 19

--

15

Repair the open in the automatic transmission shift lock control solenoid ground circuit. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 19

--

16

Replace the park/neutral position switch. Refer to Park/Neutral Position Switch Replacement in Automatic Transmission - 4T65-E.

Did you complete the replacement?

Go to Step 19

--

17

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

Did you complete the replacement?

Go to Step 19

--

18

Replace the automatic transmission shift lock control solenoid. Refer to Park Pawl Actuator Replacement in Steering Wheel and Column.

Did you complete the replacement?

Go to Step 19

--

19

Operate the system in order to verify the repair.

Did you find and correct the condition?

System OK

Go to Step 2