Contents Wiring diagrams Section: Automatic Trans All sections

Shift Interlock System Chevrolet Chevy Express G3500

Automatic Trans 3 illustrations ~889 words

Scheme 270

Scheme 270: Automatic Transmission Shift Lock Control Schematics

Scheme 271

Scheme 271: Automatic Transmission Shift Lock Control Component Views
CalloutComponent Name
1Turn Signal/Multifunction Switch Lever
2Ignition Key Cylinder
3A/T Shift Lock Control Solenoid Connector
4C200

Automatic Transmission Shift Lock Control Connector End Views

A/T Shift Lock Control Solenoid Connector End Views Connector Part Information 12052832 2-Way F Metri-Pack 150 Series (BK) Pin Wire Color Circuit No. Function A D-GN/WH 1135 A/T Shift Lock Control Solenoid Supply Voltage B BK 350 Ground

Diagnostic Starting Point - Automatic Transmission Shift Lock Control

Begin the system diagnosis by reviewing the Automatic Transmission Shift Lock Control Description and Operation . Reviewing the description and operation information will help you determine the correct symptom diagnostic procedure when a malfunction exists. Reviewing the description and operation information will also help you determine if the condition described by the customer is normal operation.

Refer to Symptoms - Automatic Transmission Shift Lock Control in order to identify the correct procedure for diagnosing the system and where the procedure is located.

Symptoms - Automatic Transmission Shift Lock Control

IMPORTANTReview 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

  1. Inspect for aftermarket devices which could affect the operation of the automatic transmission shift lock control system. Refer to «Checking Aftermarket Accessories»(/chevrolet/chevy-express-g3500/1996-2012/remont/body-electrical/#wiring-systems-diagnostic-information-and-procedures__checking-aftermarket-accessories) in Wiring Systems.
  2. 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 in Wiring Systems.

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom

  1. «Shift Lever Does Not Move with Brake Pedal Depressed»(/chevrolet/chevy-express-g3500/1996-2012/remont/automatic-trans/#shift-interlock-system__shift-lever-does-not-move-with)
  2. «Shift Lever Can Be Moved without Brake Pedal Depressed»(/chevrolet/chevy-express-g3500/1996-2012/remont/automatic-trans/#shift-interlock-system__shift-lever-can-be-moved-without)

Shift Lever Does Not Move with Brake Pedal Depressed

StepActionYesNo
Schematic Reference: Automatic Transmission Shift Lock Control Schematics Connector End View Reference: Automatic Transmission Shift Lock Control Connector End Views DEFINITION: Transmission shift lever will not move out of the PARK position with the ignition ON and the brake pedal pressed.
1Did you perform the Symptoms - Automatic Transmission Shift Lock Control tests and all the necessary inspection?Go to Step 2Go to Symptoms - Automatic Transmission Shift Lock Control
2Turn ON the ignition, with the engine OFF. Press and hold the brake pedal. 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 SystemsGo to Step 3
3Turn OFF the ignition. Disconnect the automatic transmission shift lock control switch. Turn ON the ignition, with the engine OFF. Press and hold the brake pedal. 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 5Go to Step 4
4Turn OFF the ignition. Disconnect the automatic transmission shift lock control solenoid. Turn ON the ignition, with the engine OFF. Press and hold the brake pedal. 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 7Go to Step 6
5Inspect 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 10Go to Step 8
6Inspect for poor connections at the harness connector of the automatic transmission shift lock control solenoid. 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 10Go to Step 9
7Repair the short to battery positive voltage in the automatic transmission shift control solenoid voltage supply circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair?Go to Step 10
8Replace 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
9Replace the automatic transmission shift lock control solenoid. Refer to Automatic Transmission Shift Lock Actuator Replacement . Did you complete the replacement?Go to Step 10
10Operate the system in order to verify the repair. Did you find and correct the condition?System OKGo to Step 2

Shift Lever Does Not Move with Brake Pedal Depressed

Shift Lever Can Be Moved without Brake Pedal Depressed

StepActionYesNo
Schematic Reference: Automatic Transmission Shift Lock Control Schematics Connector End View Reference: Automatic Transmission Shift Lock Control Connector End Views DEFINITION: Transmission shift lever does not lock in the PARK position with the ignition ON and the brake pedal not pressed.
1Did you perform the Symptoms - Automatic Transmission Shift Lock Control tests and all the necessary inspections?Go to Step 2Go to Symptoms - Automatic Transmission Shift Lock Control
2Apply the parking brake and block the wheels. Turn ON the ignition, with the engine OFF. Attempt to move the shift lever out of the PARK position. Does the shift lever move out of the PARK position?Go to Step 3Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems
3Turn OFF the ignition. Connect a test lamp between the Ignition 1 circuit at the park/neutral position switch and a good ground. Turn ON the ignition, with the engine OFF. Does the test lamp illuminate?Go to Step 4Go to Step 12
4Ensure transmission shift lever is in the PARK position. 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 5Go to Step 9
5Connect 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 6Go to Step 13
6Connect 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. Press and release the brake pedal several times. Does the test lamp turn ON and OFF with the brake pedal?Go to Step 7Go to Step 10
7Connect 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. Press the brake pedal. Does the test lamp illuminate?Go to Step 8Go to Step 14
8Connect 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 11Go to Step 15
9Inspect for proper park/neutral position switch adjustment. Refer to Park/Neutral Position Switch Adjustment in Automatic Transmission - 4L60-E or Park/Neutral Position Switch Adjustment in Automatic Transmission - 4L80-E. Inspect for poor connections at the harness connector of the park/neutral position 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 19Go to Step 16
10Inspect 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 19Go to Step 17
11Inspect for poor connections at the harness connector of the automatic transmission shift lock control solenoid. 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 19Go to Step 18
12Repair the open in the ignition 1 power feed circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair?Go to Step 19
13Repair the open in the park/neutral position switch park signal circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair?Go to Step 19
14Repair the open in the A/T shift lock control solenoid voltage supply circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair?Go to Step 19
15Repair the open in the automatic transmission shift lock control solenoid ground circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair?Go to Step 19
16Replace the park/neutral position switch. Refer to Park/Neutral Position Switch Replacement in Automatic Transmission - 4L60-E or Park/Neutral Position Switch Replacement in Automatic Transmission - 4L80-E. Did you complete the replacement?Go to Step 19
17Replace the automatic transmission shift lock control switch. Refer to Stop Lamp Switch Replacement in Lighting Systems. Did you complete the replacement?Go to Step 19
18Replace the automatic transmission shift lock control solenoid. Refer to Automatic Transmission Shift Lock Actuator Replacement . Did you complete the replacement?Go to Step 19
19Operate the system in order to verify the repair. Did you find and correct the condition?System OKGo to Step 2

Shift Lever Can Be Moved without Brake Pedal Depressed

Automatic Transmission Shift Lock Actuator Replacement

CAUTIONRefer to SIR Caution in Cautions and Notices.

Scheme 272

Scheme 272: Removal Procedure
  1. Disable the SIR system. Refer to «SIR Disabling and Enabling Zones»(/chevrolet/chevy-express-g3500/1996-2012/remont/airbag/#supplemental-inflatable-restraint-system__sir-disabling-and-enabling-zones) in SIR.
  2. Put the shift lever clevis into the neutral position.
  3. Remove the knee bolster. Refer to «Knee Bolster Replacement - Left»(/chevrolet/chevy-express-g3500/1996-2012/remont/gauges-instrument-panels/#instrument-panel-system-displays-gauges-and-console) in Instrument Panel, Gages, and Console.
  4. Disconnect the electrical connector.
  5. Use a small screwdriver to pry the A/T shift lock control actuator away from the steering column jacket assembly and the cable shift cam assembly.
  6. Remove the A/T shift lock control actuator.

Installation Procedure

  1. Firmly install the A/T shift lock control actuator onto the steering column jacket assembly and the cable shift cam assembly.
  2. Connect the electrical connector.
  3. Adjust the A/T shift lock control actuator with the shift lever clevis in the neutral position: Pull out the tab (1) on the adjuster block side (2) of the A/T shift lock control actuator. Press on the adjuster block (2) to compress the internal adjuster spring which disengages the adjuster teeth. Slide the adjuster block (2) as far away from the actuator as possible. Lock the adjuster block (2) in place by pushing in on the tab (1).
  4. Inspect the A/T shift lock control actuator for the following items: The A/T shift lock control actuator must lock the shift lever clevis when the shift lever clevis is put into the park position. Depress the brake pedal to move the shift lever out of the park position. The actuator will be energized. Readjust the A/T shift lock control actuator if needed.
  5. Install the knee bolster. Refer to «Knee Bolster Replacement - Left»(/chevrolet/chevy-express-g3500/1996-2012/remont/gauges-instrument-panels/#instrument-panel-system-displays-gauges-and-console) in Instrument Panel, Gages, and Console.
  6. Enable the SIR system. Refer to «SIR Disabling and Enabling Zones»(/chevrolet/chevy-express-g3500/1996-2012/remont/airbag/#supplemental-inflatable-restraint-system__sir-disabling-and-enabling-zones) in SIR.

Automatic Transmission Shift Lock Control System

The automatic transmission shift lock control is a safety device that prevents an inadvertent shift out of PARK when the ignition is ON. The driver must press the brake pedal before moving the shift lever out of the PARK position. The system consists of the following components

  1. The automatic transmission shift lock control solenoid
  2. The automatic transmission shift lock control switch
  3. The park/neutral position switch

With the ignition in the ON position, battery positive voltage is supplied to the park/neutral position switch. With the transmission in the PARK position the contacts in the park/neutral position switch are closed. This allows current to flow through the switch to the automatic transmission shift lock control switch. The circuit continues through the normally-closed switch to the automatic transmission shift lock control solenoid. The automatic transmission shift lock control solenoid is permanently grounded. This energizes the automatic transmission shift lock control solenoid, locking the shift linkage in the PARK position. When the driver presses the brake pedal the contacts in the automatic transmission shift lock control switch open, causing the automatic transmission shift lock control solenoid to de-energize. This allows the shift lever to move from the PARK position.

See also:
Checking Aftermarket Accessories
Testing for Intermittent Conditions and Poor Connections
Connector Repairs
Circuit Testing
Wiring Repairs
Stop Lamp Switch Replacement
Park/Neutral Position Switch Adjustment
Park/Neutral Position Switch Adjustment
Park/Neutral Position Switch Replacement
Park/Neutral Position Switch Replacement
SIR Caution
SIR Disabling and Enabling Zones
Knee Bolster Replacement - Left
Automatic Transmission Shift Lock Control Description and Operation
Symptoms - Automatic Transmission Shift Lock Control
Shift Lever Does Not Move with Brake Pedal Depressed
Shift Lever Can Be Moved without Brake Pedal Depressed
Automatic Transmission Shift Lock Control Connector End Views
Automatic Transmission Shift Lock Actuator Replacement