Diagnostic Instructions
| • | 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 the diagnostic category. |
DTC Descriptor
DTC B1480 00: Battery Rundown Protection CircuitDiagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Dome Lamp Switch Signal | 2 | 2 | 2 | -- |
Left Front Door Open Switch Signal | 3 | 3 | 3 | -- |
Left Rear Door Open Switch Signal | 3 | 3 | 3 | -- |
Right Front Door Open Switch Signal | 3 | 3 | 3 | -- |
Right Rear Door Open Switch Signal | 3 | 3 | 3 | -- |
Courtesy Lamp Control | 1 | 1 | -- | -- |
Courtesy Lamp Control-Driver Door | B2555 02 | 1 | B2555 01 | -- |
Courtesy Lamp Control-Passenger Door | B2555 02 | 1 | B2555 01 | -- |
Inadvertent Power Courtesy Lamp Control | 1 | 1 | 1 | -- |
Courtesy Lamp Ground-Driver Door | -- | 1 | -- | -- |
Courtesy Lamp Ground-Passenger Door | -- | 1 | -- | -- |
I/P Dimmer Switch Ground | -- | 2 | -- | -- |
LH Vanity Mirror Courtesy Lamp Ground | -- | 1 | -- | -- |
Liftgate Courtesy Lamp Ground | -- | 1 | -- | -- |
Overhead Console Courtesy Lamp Ground | -- | 1 | -- | -- |
Rear Dome Lamp Ground | -- | 1 | -- | -- |
RH Vanity Mirror Courtesy Lamp Ground | -- | 1 | -- | -- |
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Circuit/System Description
The CTSY/LAMP fuse supplies battery voltage to the body control module (BCM). The BCM applies battery voltage to the courtesy lamps through the courtesy lamp supply voltage circuit. When any door is opened, the jam switch contacts close and the BCM receives a door-open input. If the BCM receives a door lock or unlock input or a rear hatch open input, the BCM will activate the courtesy lamp supply voltage circuit, providing battery voltage to all of the instrument panel (I/P) courtesy lamps, dome lamps, rearview mirror lamps, and rear compartment lamps. The BCM also provides a GMLAN serial data message to the driver door module (DDM) and front passenger door module (PDM) to apply battery voltage to the door courtesy lamps. In the event that any of these lamps were to remain illuminated for more than 20 minutes with the ignition switch in the OFF position, the BCM will deactivate the inadvertent power courtesy lamp control circuit to prevent a total battery discharge condition.
Conditions for Running the DTC
Battery voltage must be between 9-16 volts.
Conditions for Setting the DTC
DTC B1480 will set when the courtesy lamp supply voltage circuit that feeds the courtesy lamps, dome lamps, overhead console lamp, liftgate lamp and rear dome lamp is shorted to ground for longer than 1 second.
Actions Taken When the DTC Sets
The courtesy lamps will not operate.
Conditions for Clearing the DTC
| • | The condition responsible for setting the DTC no longer exists. |
| • | A history DTC will clear once 100 consecutive malfunction-free ignition cycles have occurred. |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Interior Lighting Systems Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing
- Ignition OFF, disconnect the appropriate harness connector at each component fed by the inadvertent power courtesy lamp control circuit.
- Ignition ON, verify that a test lamp illuminates between the inadvertent power courtesy lamp control circuit at each component harness connector and ground.
- Connect each component one at a time and verify with a scan tool if the DTC resets as current.
| ⇒ | If the test lamp does not illuminate, test the inadvertent power courtesy lamp control circuit for a short to ground or an open/high resistance. If the circuits test normal, replace the BCM. |
| ⇒ | If the DTC resets as current, test or replace the component responsible for setting the DTC. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM replacement, setup, and programming |
