Contents Wiring diagrams Section: Automatic Trans All sections

Shift Lock Control System: Other Chevrolet Silverado 1500

Automatic Trans ~133 words

Intermittent

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

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 , Automatic Transmission Related Connector End Views or Automatic Transmission Related 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 .Go 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 6Go 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 5
5Inspect 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 . Did you find and correct the condition?Go to Step 10Go to Step 9
6Inspect 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 . Did you find and correct the condition?Go to Step 10Go to Step 8
7Repair the short to battery positive voltage in the A/T shift lock control solenoid supply voltage circuit. Refer to Circuit Testing and Wiring Repairs . Did you complete the repair?Go to Step 10
8Replace the automatic transmission shift lock control switch. Refer to Stop Lamp Switch Replacement . Did you complete the replacement?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 (w/o Allison Transmission)

StepActionYesNo
Schematic Reference: Automatic Transmission Shift Lock Control Schematics Connector End View Reference: Automatic Transmission Shift Lock Control Connector End Views , Automatic Transmission Related Connector End Views or Automatic Transmission Related 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 .
3Turn OFF the ignition. Ensure transmission shift lever is in the PARK position. Connect a test lamp between the A/T shift lock switch supply voltage circuit at the BTSI fuse and a good ground Turn ON the ignition, with the engine OFF. Does the test lamp illuminate?Go to Step 4Go to Step 8
4Connect a test lamp between the A/T shift lock switch supply voltage circuit at the automatic transmission shift lock control switch and a good ground Does the test lamp illuminate?Go to Step 5Go to Step 14
5Connect a test lamp between the A/T shift lock solenoid control 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 6Go to Step 11
6Connect a test lamp between the automatic transmission shift lock control solenoid supply voltage circuit at the automatic transmission shift lock control solenoid and a good ground. Does the test lamp illuminate?Go to Step 7Go to Step 15
7Test the automatic transmission shift lock control solenoid ground circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 20Go to Step 12
8Turn OFF the ignition Disconnect the park/neutral position switch connector. Connect a test lamp between the ignition 1 voltage circuit of 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 9Go to Step 13
9Turn OFF the ignition Connect a 10 amp fused jumper between the ignition 1 voltage circuit of the park/neutral position switch and the park/neutral position switch park signal circuit at the park/neutral position switch connector. Connect a test lamp between the A/T shift lock switch supply circuit at the BTSI fuse and a good ground. Turn ON the ignition, with the engine OFF. Does the test lamp illuminate?Go to Step 10Go to Step 16
10Inspect for proper park/neutral position switch adjustment. Refer to Park/Neutral Position Switch Adjustment with 4L60-E transmission or Park/Neutral Position Switch Adjustment with 4L80-E transmission. 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 . Did you find and correct the condition?Go to Step 20Go to Step 17
11Inspect 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 . Did you find and correct the condition?Go to Step 20Go to Step 18
12Inspect for poor connections at the harness connector automatic transmission shift lock control solenoid. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 20Go to Step 19
13Repair the open or short in the ignition 1 voltage circuit of the park/neutral position switch. Refer to Circuit Testing and Wiring Repairs . Did you complete the repair?Go to Step 20
14Repair the open or short in the A/T shift lock switch supply voltage circuit. Refer to Circuit Testing and Wiring Repairs . Did you complete the repair?Go to Step 20
15Repair the open in the A/T shift lock control solenoid supply voltage circuit. Refer to Circuit Testing and Wiring Repairs . Did you complete the repair?Go to Step 20
16Repair the open or short in the park/neutral position switch park signal circuit. Refer to Circuit Testing and Wiring Repairs . Did you complete the repair?Go to Step 20
17Replace the park/neutral position switch. Refer to Park/Neutral Position Switch Replacement with 4L60-E transmission or Park/Neutral Position Switch Replacement with 4L80-E transmission. Did you complete the replacement?Go to Step 20
18Replace the automatic transmission shift lock control switch. Refer to Stop Lamp Switch Replacement . Did you complete the replacement?Go to Step 20
19Replace the automatic transmission shift lock control solenoid. Refer to Automatic Transmission Shift Lock Actuator Replacement . Did you complete the replacement?Go to Step 20
20Operate 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 (w/o Allison Transmission)

Circuit/System Verification

With a scan tool, monitor the Trans. Range Sw. data to verify vehicle is in the Park position.

  1. If data does not display Park, replace the internal mode switch (IMS). Refer to «Transmission Internal Mode Switch Replacement»(ref-238244-S23495787312006072400000) .

Repair Instructions

IMPORTANTAlways perform the Diagnostic Repair Verification after completing the diagnostic procedure.
  1. «Stop Lamp Switch Replacement»(ref-238182-S10595482002006072400000)
  2. «Automatic Transmission Shift Lock Actuator Replacement»(ref-238252-S07774227952006072400000)
  3. «Transmission Internal Mode Switch Replacement»(ref-238244-S23495787312006072400000)
  4. «Body Control Module Replacement»(ref-238179-S13881127862006072400000) for BCM