GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Saturn 🢒 2007 🢒 RELAY Ext. 🢒 Brakes 🢒 Park Brake 🢒 DTC B1475

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 provides battery negative voltage to the RAP relay control circuit. When the RAP relay is energized, it supplies a B+ to the accessories not controlled by a serial data power mode message.

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.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B1475 Retained Accessory Power Circuit

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 supply voltage circuit 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.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. Listen for an audible click when the RAP relay operates. Command both the ON and OFF states. Repeat the commands, as necessary.

    2.

  2. This step tests for voltage at the coil side of the RAP relay. The RAP fuse supplies power to the coil side of the RAP relay.

    3.

  3. This step verifies that the BCM is providing ground to the RAP relay.

    4.

  4. This step tests the control circuit side of the RAP relay for faults that cause both B1475 RAP DTC.

    5.

  5. After replacement of the BCM you must calibrate the new module for proper operation.

Step

Action

Yes

No

Schematic Reference: Power Distribution Schematics

Connector End View Reference: Master Electrical Component List

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, command the retained accessory power (RAP) relay ON and OFF.

Does the RAP relay turn ON and OFF with each command?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

  1. Turn OFF the ignition.
  2. Remove the RAP relay.
  3. Turn the ignition ON, with the engine OFF.
  4. Test the control circuit of the RAP relay for voltage and ground as required by the schematic. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 11

Go to Step 4

4

  1. Connect a test lamp between the RAP relay control circuit at the RAP relay socket and the battery positive voltage circuit of the RAP relay.
  2. With a scan tool, command the RAP relay ON and OFF .

Does the test lamp turn On and Off?

Go to Step 6

Go to Step 5

5

Test the control circuit of the RAP relay for the following conditions:

    • A short to ground
    • A short to battery positive voltage
    • An open circuit

Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 11

Go to Step 7

6

Inspect for poor connections and terminal damage at the RAP relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 11

Go to Step 9

7

Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 11

Go to Step 10

8

Repair the non control circuit of the RAP relay. Refer to Wiring Repairs .

Did you complete the repair?

Go to Step 11

--

9

Replace the RAP relay.

Did you complete the replacement?

Go to Step 11

--

10

Replace the BCM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 11

--

11
  1. Use the scan tool in order to clear the DTCs .
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK