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For 1990-2009 cars only
Makes 🢒 Buick 🢒 2006 🢒 Lucerne 🢒 Vehicle Control Systems 🢒 Computer/Integrating Systems 🢒 DTC B1475

DTC Descriptor

DTC B1475 00: Retained Accessory Power Circuit

Diagnostic Fault Information

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

RAP Relay Coil Supply Voltage

B1475 00

1

1

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1. Retained Accessory Power (RAP) Malfunction

Circuit/System Description

The body control module (BCM) controls the R1 RAP relay through the rap relay coil supply voltage circuit by applying voltage to the coil side of the relay. The R1 RAP relay is energized when any of the following conditions are true:

    • Ignition switch is in ACC or ON.
    • The vehicle was remote started.
    • The vehicle is in RAP mode.

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 in the rap relay coil supply voltage circuit.

Action Taken When the DTC Sets

The module 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
    • Use the DMM MIN/MAX function to capture/locate intermittent conditions.
    • The radio RAP mode is separate function and will still operate properly.
    • The ignition switch will not return to the OFF position if the RAP relay does not energize.

Reference Information

Schematic Reference

    •  Body Control System Schematics
    •  Power Distribution Schematics

Connector End View Reference

Computer/Integrating Systems Connector End Views

Electrical Information Reference

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

Circuit/System Testing
  1. Disconnect the R1 RAP relay and connect a test lamp between the rap relay coil supply voltage circuit and ground.
  2. Ignition ON. The test lamp should turn ON.
    3. ⇒If the test lamp remains OFF, test for a short to ground the relay control circuit. If the circuit tests normal, replace the BCM.
    ⇒If the test lamp turns ON, test or replace the RAP relay.
  3. If the circuit tests normal and the DTC is current, test or replace the R1 RAP relay or BCM.

Component Testing

Rap Relay Test

  1. Ignition OFF, disconnect the R1 RAP relay.
  2. Test for 70-110 ohms of resistance between terminals 85 and 86.
    3. ⇒If the resistance is not within the specified range, replace the relay.
  3. Test for infinite resistance between the following terminals:
    4. • 30 and 86
    • 30 and 87
    • 30 and 85
    • 85 and 87
    ⇒If less than infinite, replace the relay.
  4. Install a 20-amp fused jumper wire between relay terminal 85 and 12 volts. Install a jumper wire between relay terminal 86 and ground. Test for less than 5 ohms of resistance between terminals 30 and 87.
    5. ⇒If greater than 5 ohms, replace the relay.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for BCM replacement, setup, and programming