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For 1990-2009 cars only
Makes 🢒 Buick 🢒 2008 🢒 Enclave - AWD 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Retained Accessory Power Malfunction

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

Ignition I/II Voltage

B1475, 1

1

2

--

  1. All or some BCM direct wired RAP functions inoperative, depending on the location of the open.
  2. BCM direct wired RAP remains on past the timer limit after key out and will not turn off when a vehicle door is opened.

Circuit/System Description

The retained accessory power (RAP) system allows specific vehicle functions to operate after the ignition is turned OFF for a predetermined time. The RAP function is directly controlled by the BCM through the ignition I/II voltage circuit. RAP is controlled by the BCM using inputs from the door ajar switches to determine control of the ignition I/II voltage circuit when the ignition is turned OFF. Radio RAP is controlled by a serial data message from the BCM using inputs from the driver door open switch. The ignition I/II voltage circuit from the BCM feeds the following:

    • Automatic transmission shift lever
    • Sunroof shade module (with RPO C3U)
    • Sunroof control module (with RPO C3U)
    • Inside rearview mirror (with RPO DD7/DD8)
    • Auxiliary power outlet -- 115V AC (with RPO KVI)
    • Driver window switch (without RPO AXC/AXE)
    • Passenger window switch (without RPO AXC/AXE)

Diagnostic Aids
    • The radio RAP function is a separate RAP function controlled by serial data and the specific module. These functions are not effected by the BCM ignition I/II voltage circuit.
    • An open/high resistance in the ignition I/II voltage circuit may cause only part of the RAP functions to be inoperative. Diagnose these symptoms within the respective system sections.
    • A short to voltage on the ignition I/II voltage circuit would cause the RAP function to remain on past the designated time.

Reference Information

Schematic Reference

Power Moding Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Retained Accessory Power (RAP) 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

Important: Battery voltage must remain above 9.6 V for RAP to operate properly.

Radio RAP

  1. With all passenger doors closed, observe the courtesy lamps while opening and closing the driver door. The courtesy lamps should illuminate when the door is opened and turn off approximately 30 seconds after closing the door.
    2. ⇒If the courtesy lamp operation is incorrect from the drivers door, refer to Courtesy Lamps Malfunction .
  2. If courtesy lamp operation is correct, and the radio is the only RAP concern, replace the radio.

BCM Direct Wired RAP

  1. With a scan tool, verify that BCM DTC B1475 is not set.
    2. ⇒If DTC B1475 is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle.
  2. Ignition ON, observe the appropriate scan tool parameters listed below while opening and closing each vehicle door. The reading should change between Door Closed/Door Ajar.

    3. Parameter

    • Driver Door Ajar Sw.
    • Left Rear Door Ajar Sw.
    • Passenger Door Ajar Sw.
    • Right Rear Door Ajar Sw.
    ⇒If any parameter does not change as specified, refer to Door Ajar Indicator Malfunction .
  3. Command the scan tool Accy/RAP Relay OFF. Attempt to operate any BCM direct wired RAP controlled component within 5 seconds. The component should not operate.
  4. Command the scan tool Accy/RAP Relay ON. Attempt to operate any BCM direct wired RAP controlled component within 5 seconds. The component should operate.
  5. Ignition ON, all doors closed. Observe the scan tool parameter Accy/RAP Relay Command. Ignition OFF, key removed, the reading should be ON for approximately 10 minutes then change to OFF.
    6. ⇒If the parameter does not respond as specified, replace the BCM.

Circuit/System Testing
  1. Ignition OFF, disconnect the harness connector at the automatic transmission shift lever.
  2. With the ignition key out of the ignition and the driver door open, verify a test lamp does not illuminate between the ignition I/II voltage circuit terminal Z1 at the automatic transmission shift lever harness connector and ground.
    3. ⇒If the test lamp illuminates, test the ignition circuit for a short to voltage. If the circuit tests normal, test or replace the BCM

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for module replacement, setup, and programming