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 each diagnostic category. |
DTC Descriptor
DTC B1517 5A: Battery Voltage Plausibility FailureDiagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
BCM 2 B+ | B1517 5A | B1325 03, B1517 5A | -- | -- |
SDM or XM/ONSTAR B+ | B1517 5A | B1517 5A | -- | -- |
Ground | -- | B1517 5A | -- | -- |
Typical Scan Tool Data
Circuit | Short to Ground | Open | Short to Voltage |
|---|---|---|---|
Operating Conditions: Key On, Engine Off. Parameter Normal Value: 12.60 Volts | |||
BCM 2 B+ | 0.00 Volts* | 0.00 Volts* | 12.60 Volts |
*The BCM, EBCM, ECM, IPC, PSCM, TCM and TDM will not communicate if there is 0 volts on this circuit. | |||
Circuit | Short to Ground | Open | Short to Voltage |
|---|---|---|---|
Operating Conditions: Key On, Engine Off. Parameter Normal Value: 12.600 Volts | |||
SDM or XM/ONSTAR B+ | 0.000 Volts* | 0.000 Volts* | 12.600 Volts |
*The DRR and VCIM will not communicate if there is 0 volts on this circuit. | |||
Circuit/System Description
The body control module (BCM) has designated B+ circuits for monitoring vehicle system voltage, fed by the BCM 2 fuse and the SDM or XM/ONSTAR fuse. Fuse 24 in the BCM will either be labeled SDM or XM/ONSTAR, depending on vehicle content. The BCM monitors the system voltage to ensure that the voltage stays within the proper range. Damage to components and incorrect data may occur when the voltage is out of range. The BCM monitors the system voltage over an extended length of time. If the BCM detects the system voltage is outside an expected range for the calibrated length of time, or the BCM battery sense circuits differ by 3 volts, DTC B1517 5A will set. Other modules also monitor system voltage. The system voltage message is sent to the other modules and will default to 12.9 volts if DTC B1517 5A sets.
Conditions for Running the DTC
| • | The BCM has power and ground |
| • | The ignition switch is not in the start position |
Conditions for Setting the DTC
The battery voltage on the BCM battery sense circuits differs by 2 volts for 10 seconds.
Action Taken When the DTC Sets
The regulated voltage control (RVC) is disabled.
Conditions for Clearing the DTC
| • | The DTC will pass when the condition for setting the DTC is no longer present. |
| • | A history DTC will clear after 50 consecutive ignition cycles have occurred without a malfunction. |
Diagnostic Aids
| • | A low voltage DTC in multiple modules indicates a concern in the charging system. |
| • | Inspect the SDM or XM/ONSTAR fuse for an open. |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Charging System Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- Engine running, accessories OFF, measure and record the battery voltage at the battery terminals. The voltage should be between 12.6 and 15.0 volts.
- Observe the scan tool BCM Battery Voltage Signal parameter and the Batt. Voltage High Res. parameter. The reading for both parameters should be between 12.6 and 15.0 volts, and should be within 2 volts of each other.
| ⇒ | If not within the specified range, refer to Charging System Test. |
Circuit/System Testing
- Verify that a test lamp illuminates between the SDM or XM/ONSTAR fuse 24 in the BCM and ground.
- Ignition OFF, disconnect the harness connectors at the BCM.
- Test for less than 5 ohms between the ground circuit terminal E12 X4 and ground.
- Verify that a test lamp illuminates between the B+ circuit terminals listed below and ground.
- Test for less than 5 ohms between the B+ circuit terminal 62 X1 and terminal B3 X3.
- If all circuits test normal, replace the BCM.
| ⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. |
| ⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
| • | Terminal D1 X3 |
| • | Terminal D12 X3 |
| ⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. |
| ⇒ | If greater than the specified range, test the B+ circuit for an open/high resistance. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for BCM replacement, setup, and programming.
