• | 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. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage |
---|---|---|---|
Battery Positive Voltage | B1475 | B1475 | -- |
Rap Relay Control | -- | B1475 | B1475 |
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.
The system voltage must be between 9-16 volts.
• | 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. |
• | The BCM stores DTC B1475 in memory. |
• | The devices powered by the RAP relay will not operate. |
• | 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. |
Master Electrical Component List
Retained Accessory Power (RAP) Description and Operation
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.
⇒ | 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. |
⇒ | 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. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for module replacement, setup, and programming |