B1475

DTC B1475

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview)provides an overview of each diagnostic category.



DTC Descriptor
DTC B1475
- Retained Accessory Power Circuit




Diagnostic Fault Information






Circuit Description

The body control module (BCM) controls various accessories through the retained accessory power (RAP) relay circuit. When the ignition switch is in either the ACC or the ON position, the BCM grounds the RAP relay control circuit, energizing the RAP relay. When the RAP relay is energized, it supplies a B+ to the various accessories.


When the ignition switch turns from ON or ACC to OFF, with all of the vehicle doors closed, the BCM keeps the relay energized for 10 minutes, or until any vehicle door opens.


Conditions for Running the DTC

The system voltage must be between 9-16 volts.


Conditions for Setting the DTC

* The BCM detects a short to voltage in the RAP relay control circuit when the BCM is trying to energize the relay.
* The BCM detects that the RAP relay control circuit is open.
* The condition above must be present for more than 1 second.



Action Taken When the DTC Sets

* The BCM stores DTC B1475 in memory.
* The devices powered by the RAP relay will not operate.



Conditions for Clearing the DTC

* A current DTC clears when the malfunction is no longer present.
* A history DTC clears when the module ignition cycle counter reaches the reset threshold, without a repeat of the malfunction.



Reference Information
Schematic Reference

Power Distribution Schematics (Power Distribution Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Retained Accessory Power (RAP) Description and Operation (Retained Accessory Power (RAP) Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning)for Scan Tool Information


Circuit/System Verification

Ignition ON, command the retained accessory power (RAP relay) ON and OFF with a scan tool. Feel/listen for the operation of the RAP relay.


Circuit/System Testing

1. Ignition OFF, disconnect the RAP Relay.
2. Verify that a test lamp illuminates between the B+ circuit terminals M3 and ground and between terminals N3 and ground.

• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, test the accessory voltage circuit terminal M1 for a short to ground. If the circuit tests normal, test or replace the RAP relay.

3. Connect a test lamp between the B+ circuit terminal M3 and the RAP relay control circuit terminal N1.
4. Command the RAP relay ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.

• If the test lamp is always ON, test the RAP relay control circuit for a short to ground. If the circuit tests normal, replace the BCM.


• If the test lamp is always OFF, test the RAP relay control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.

5. If all circuits test normal, test or replace the RAP relay.



Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Control Module References (Programming and Relearning)for module replacement, setup, and programming
* Relay Replacement (Attached to Wire Harness) (Relay Replacement (Attached to Wire Harness))Relay Replacement (Within an Electrical Center) (Relay Replacement (Within an Electrical Center))