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Shift Lock Control System: Diagnosis Saturn Astra I

Automatic Trans ~714 words

Diagnostic Starting Point - Automatic Transmission Shift Lock Control

Begin the system diagnosis with the Diagnostic System Check - Vehicle . The Diagnostic System Check will provide the following information

  1. The identification of the control modules which command the system
  2. The ability of the control modules to communicate through the serial data circuit
  3. The identification of any stored diagnostic trouble codes (DTCs) and their status

The use of the Diagnostic System Check will identify the correct procedure for diagnosing the system and where the procedure is located.

Symptoms - Automatic Transmission Shift Lock Control

IMPORTANTThe following steps must be completed before using the symptom tables.
  1. Perform the «Diagnostic System Check - Vehicle»(ref-302315-S22962940552008102100000) 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.
  2. Review the system operation in order to familiarize yourself with the system functions. Refer to «Automatic Transmission Shift Lock Control Description and Operation»(ref-302349-S41636412672008102100000) .

Visual/Physical Inspection

  1. Inspect for aftermarket devices which could affect the operation of the automatic transmission shift lock control. Refer to «Checking Aftermarket Accessories»(ref-302317-S19452665262008102100000) .
  2. Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

Symptom List

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

Transmission Control Lever Malfunction

Diagnostic Instructions

  1. Perform the «Diagnostic System Check - Vehicle»(ref-302315-S22962940552008102100000) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(ref-302315-S32068625472008102100000) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(ref-302315-S09719072712008102100000) provides an overview of each diagnostic category.

Diagnostic Fault Information

CircuitShort to GroundOpen/High ResistanceShort to VoltageSignal Performance
Automatic Transmission Park Interlock Relay Ignition Voltage113
Automatic Transmission Park Interlock Relay Signal112
Automatic Transmission Park Interlock Relay Ground1
Shift Lock Control Solenoid Control112
Park Lock Solenoid Ground1
1. Gear shift selector will not move from the PARK position with brake applied 2. Gear shift selector moves from the PARK position w/o brake applied 3. Gear shift selector moves from the PARK position w/brake applied and ignition OFF.

Diagnostic Aids

If the automatic transmission shift lock control circuit is open, the A/T shift lock solenoid will be inoperative. The vehicle will not shift out of PARK with or without depressing the brake pedal.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the automatic transmission park interlock relay.
  2. Ignition OFF, test for less than 1.0 ohm between the ground circuit terminal 2 and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, verify that a test lamp illuminates between the relay ignition supply voltage circuit terminal 1 and ground. If the test lamp does not illuminate, test for an open or short to ground in the ignition supply voltage circuit. If the circuit tests normal, test or replace the relay.
  4. Ignition ON, depress brake pedal, verify that a test lamp illuminates between the relay signal circuit terminal 5 and ground. If the test lamp does not illuminate, test for an open or short to ground in the relay signal circuit or a short to ground in the automatic transmission shift lock control solenoid control circuit. If the circuits test normal, perform the automatic transmission shift lock solenoid component test. If the solenoid tests normal, replace the stoplamp switch.
  5. Ignition OFF, disconnect the harness connector at the automatic transmission shift lock control solenoid.
  6. Ignition OFF, test for less than 1.0 ohm between the ground circuit terminal 6 and ground. If greater than the specified range, test the ground circuit for an open/high resistance.
  7. Ignition OFF, verify that a test lamp does not illuminate between the solenoid control circuit terminal 8 and ground. If the test lamp illuminates, test the automatic transmission park interlock relay signal circuit and the automatic transmission shift lock control solenoid control circuits for a short to B+.
  8. Ignition OFF, depress the brake pedal, verify that a test lamp does not illuminate between the control circuit terminal 8 and ground. If the test lamp illuminates, test for a short to B+ in the relay ignition supply voltage circuit. If the circuit tests normal, test or replace the automatic transmission park interlock relay.
  9. Ignition ON, brake pedal not depressed, verify that a test lamp does not illuminate between the control circuit terminal 8 and ground. If the test lamp illuminates, test or replace the stoplamp switch.
  10. Test or replace the automatic transmission shift lock control solenoid.

Component Testing

  1. Install a 10 A fused jumper wire from 12 volts to the automatic transmission shift lock solenoid control circuit terminal 8. Momentarily connect a jumper wire from ground to terminal 6.
  2. Listen for the solenoid to turn ON and OFF. If the function does not perform as specified, replace the automatic transmission shift lock solenoid.

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