Diagnostic Instructions
DTC Descriptor
DTC B1477 00: Retained Accessory Power Circuit
Diagnostic Fault Information
Circuit
| Short to Ground
| Open/High Resistance
| Short to Voltage
| Signal Performance
|
Retained Accessory Power (RAP) Supply Voltage Circuit
| B1477, 1
| 1
| 2
| --
|
- The sunroof will not operate.
- The sunroof will remains on past the timer limit after key out and will not turn off when a vehicle door is opened.
|
Circuit/System Description
The body control module (BCM) controls the sunroof motor operation through the retained accessory power (RAP) supply voltage circuit. When the ignition switch is in either the ACC or the ON position, the BCM provides battery voltage to the RAP supply voltage
circuit. When the ignition switch turns from ON or ACC to OFF, with all of the vehicle doors closed, the BCM still provides battery voltage to the circuit for 10 minutes, or until any vehicle door opens.
| • | 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.
Conditions for Setting the DTC
| • | The BCM detects a short to ground in the RAP supply voltage circuit when the BCM is trying to energize the circuit. |
| • | The condition above must be present for more than 1 second. |
Action Taken When the DTC Sets
| • | The BCM stores DTC B1477 in memory. |
| • | The sunroof will not operate. |
Conditions for Clearing the DTC
| • | The current DTC will clear 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 Moding Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Retained Accessory Power (RAP) Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for Scan Tool Information
Circuit/System Testing
- Ignition ON, verify DTC B1477 is set as current.
| ⇒ | If DTC B1477 is not set as current, operate the vehicle within the Conditions for Setting the DTC. |
- Ignition OFF, disconnect the harness connector of the sunroof module.
- Ignition ON, verify DTC B1477 remains set as current.
| ⇒ | If DTC B1477 does not remain set as current, test or replace the sunroof motor. |
- Test the retained accessory power (RAP) supply voltage circuit for a short to ground. If the circuit tests normal, test or replace the BCM.
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic procedure.
