GM Service Manual Online
For 1990-2009 cars only

DTC Descriptor

DTC B3006 5A: Hood Ajar Circuit Plausibility Failure

Diagnostic Fault Information

Important: Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Circuit/System Description

The BCM uses this input signal to determine if the hood is open or closed. When the hood is closed, voltage passes through the hood. The voltage is seen by the BCM as the hood closed input signal. In the event of a open circuit in either circuit 109 or 5531, the BCM internal pull down resistor ensures the voltage at the input to the microprocessor is less than 0.2V. This low voltage at the microprocessor is seen as the hood open signal.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

The BCM receives a voltage signal on the hood switch.

Action Taken When the DTC Sets

The alarm will trigger.

Conditions for Clearing the DTC

The BCM clears this code from current when the fault is removed from the system.

Reference Information

Schematic Reference

Door Lock/Indicator Schematics .

Connector End View Reference

Component Connector End Views

Electrical Information Reference

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

Scan Tool Reference

Control Module References

Circuit/System Testing

  1. Ignition OFF, disconnect the S135 circuit 109 and S135 circuit 5531. Using a DMM measure the resistance, probe between the hood switch S135 circuit 109 and S135 circuit 5531 and a known ground. Does the DMM display resistance (both circuits).
  2. If no resistance replace the hood switch.
  3. With the hood switch (S135) connectors still disconnected, check for a short to ground or open circuit in circuits 109 and 5531.
  4. If a short to ground or open circuit, replace the BCM otherwise repair the circuit 109 or 5531 as required. Replace the S135 connectors.

Repair Instructions

Important: Always perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Door Lock Cylinder Replacement
    •  Front Side Door Inside Handle Replacement
    •  Rear Side Door Inside Handle Replacement
    •  Control Module References