GM Service Manual Online
For 1990-2009 cars only

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.

DTC Descriptor

DTC B1475 00: Retained Accessory Power Circuit

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Accessory Voltage

B1475 00

1

2

--

  1. Partial or all relay controlled RAP functions inoperative depending on location of open.
  2. Relay 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 relay is internal to the BCM. Relay RAP is controlled by the BCM using inputs from the door ajar switches to determine control of the relay 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. Refer to Retained Accessory Power (RAP) Description and Operation for more detail on RAP operation.

Conditions for Running the DTC

    • The system voltage is between 9-16 volts.
    • The DTC can only set when the output is actively being requested by the module.

Conditions for Setting the DTC

The DTC will set only when the module requests the output and there is a short to ground detected in the RAP supply voltage circuit.

Action Taken When the DTC Sets

The BCM output driver will be shut down and not supply voltage to the circuit.

Conditions for Clearing the DTC

    • The current DTC will clear when the module request for the output is removed or the malfunction is no longer present.
    • A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.

Diagnostic Aids

    • The RAP/Spare relay is permanently soldered to the left I/P junction block and is non-serviceable.
    • The RAP mode for the radio and door modules is a separate function and will still operate properly.

Reference Information

Schematic Reference

Power Moding Schematics

Connector End View Reference

Power and Grounding Connector End Views

Electrical Information Reference

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

Circuit/System Testing

  1. Ignition ON, verify DTC B1475 is set as current.
  2. If DTC B1475 is not set as current, operate the vehicle within the Conditions for Setting the DTC.

    Important: When cycling the ignition, keep ignition OFF for 5 seconds before checking for current DTC.

  3. Disconnect each of the following components one at a time. The components may be disconnected in any order. After each component is disconnected, cycle the ignition and verify DTC B1475 remains set as current.
  4. • Sunroof module (with RPO CF5)
    • Mobile radio relay A (with RPO 9L4)
    If DTC B1475 does not remain set as current, test or replace the last component that was disconnected.
  5. With all components disconnected, cycle the ignition and verify DTC B1475 is not set as current.
  6. If DTC B1475 remains set as current, test the accessory voltage circuit for a short to ground. If the circuit tests normal, replace the BCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Instrument Panel Electrical Center or Junction Block Replacement - Left Side
    •  Control Module References for module replacement, setup, and programming