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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2009 🢒 Captiva Sport 🢒 Safety and Security 🢒 Immobilizer 🢒 Hood Ajar Indicator/Message Malfunction

Hood Ajar Indicator/Message Malfunction without HP7

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Hood Ajar Switch Signal

1

1

1

--

Hood Closed Switch Signal

1

1

1

--

Ground

--

1

--

--

1. Hood ajar switch malfunction

Circuit/System Description

The body control module (BCM) monitors the voltage input of the hood open switch signal circuit and the hood open closed switch signal circuit. With the hood open, the hood ajar portion of the switch is closed, grounding the hood ajar switch signal circuit from the BCM, and the hood closed portion of the switch is open. With the hood closed, the hood closed portion of the switch is closed, grounding the hood closed switch signal circuit from the BCM, and the hood ajar portion of the switch is open. During proper operation, the two separate voltage signals at the BCM should never be at the same voltage.

Reference Information

Schematic Reference

    •  Immobilizer Schematics
    •  Remote Function Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Keyless Entry System Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Ignition ON, observe the scan tool BCM Hood Open Switch and Hood Closed Switch parameters. With the hood open, the Hood Open Switch parameter should read Active and the Hood Closed Switch parameter should read Inactive. With the hood closed, the Hood Open Switch parameter should read Inactive and the Hood Closed Switch parameter should read Active.

Circuit/System Testing
  1. Ignition OFF, disconnect the harness connector at the hood ajar switch.
  2. Ignition OFF, test for less than 5 ohms between the ground circuit terminal A and ground.
    3. ⇒If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, test for 11.5-12.0 volts between the signal circuit terminal B and ground.
    4. ⇒If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the BCM.
    ⇒If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
  4. Ignition ON, test for 11.5-12.0 volts between the signal circuit terminal C and ground.
    5. ⇒If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the BCM.
    ⇒If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
  5. If all circuits test normal, test or replace the hood ajar switch.

Component Testing

Hood Ajar Switch

  1. Ignition OFF, disconnect the harness connector at the hood ajar switch.
  2. With the switch in the hood closed position, test for infinite resistance between the ground terminal A and the signal terminal B.
    3. ⇒If not the specified value, replace the hood ajar switch.
  3. Test for less than 2.0 ohms between the ground terminal A and the signal terminal C.
    4. ⇒If greater than the specified range, replace the hood ajar switch.
  4. With the switch in the hood open position, test for infinite resistance between the ground terminal A and the signal terminal C.
    5. ⇒If not the specified value, replace the hood ajar switch.
  5. Test for less than 2.0 ohms between the ground terminal A and the signal terminal B.
    6. ⇒If greater than the specified range, replace the hood ajar switch.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Hood Primary and Secondary Latch Replacement
    •  Control Module References for BCM or instrument cluster replacement, programming and setup

Hood Ajar Indicator/Message Malfunction with HP7

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Hood Ajar Switch Signal

1

1

1

--

Hood Closed Switch Signal

1

1

1

--

Ground

--

1

--

--

1. Hood ajar switch malfunction

Circuit/System Description

The starter/generator control module (SGCM) monitors the voltage input of the hood open switch signal circuit and the hood open closed switch signal circuit. With the hood open, the hood ajar portion of the switch is closed, grounding the hood ajar switch signal circuit from the ECM, and the hood closed portion of the switch is open. With the hood closed, the hood closed portion of the switch is closed, grounding the hood closed switch signal circuit from the SGCM, and the hood ajar portion of the switch is open. During proper operation, the two separate voltage signals at the SGCM should never be at the same voltage.

The hood ajar switch status is also sent to the engine control module (ECM) via serial data.

Reference Information

Schematic Reference

Immobilizer Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Keyless Entry System Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Ignition ON, observe the scan tool SGCM Hood Position parameter. With the hood open, the Hood Position parameter should read Open. With the hood closed, the Hood Position parameter should read Closed.

Circuit/System Testing
  1. Ignition OFF, disconnect the harness connector at the hood ajar switch.
  2. Ignition OFF, test for less than 10 ohms between the ground circuit terminal A and ground.
    3. ⇒If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, test for 10.0-12.5 volts between the signal circuit terminal B and ground.
    4. ⇒If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the SGCM.
    ⇒If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the SGCM.
  4. Ignition ON, test for 10.0-12.5 volts between the signal circuit terminal C and ground.
    5. ⇒If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the SGCM.
    ⇒If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the SGCM.
  5. Ignition OFF, connect the harness connector at the hood ajar switch.
  6. Ignition ON, observe the scan tool SGCM Hood Position parameter. With the hood open, the Hood Position parameter should read Open. With the hood closed, the Hood Position parameter should read Closed.
    7. ⇒If the parameter does not change between the specified values, test or replace the hood ajar switch.
  7. Observe the scan tool ECM Hood Position parameter. With the hood open, the Hood Position parameter should read Open. With the hood closed, the Hood Position parameter should read Closed.
    8. ⇒If the parameter does not change between the specified values, replace the ECM.
  8. If all circuits test normal, test or replace the hood ajar switch.

Component Testing

Hood Ajar Switch

  1. Ignition OFF, disconnect the harness connector at the hood ajar switch.
  2. With the switch in the hood closed position, test for infinite resistance between the ground terminal A and the signal terminal B.
    3. ⇒If not the specified value, replace the hood ajar switch.
  3. Test for less than 2.0 ohms between the ground terminal A and the signal terminal C.
    4. ⇒If greater than the specified range, replace the hood ajar switch.
  4. With the switch in the hood open position, test for infinite resistance between the ground terminal A and the signal terminal C.
    5. ⇒If not the specified value, replace the hood ajar switch.
  5. Test for less than 2.0 ohms between the ground terminal A and the signal terminal B.
    6. ⇒If greater than the specified range, replace the hood ajar switch.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Hood Primary and Secondary Latch Replacement
    •  Control Module References for ECM or SGCM replacement, programming, and setup