For 1990-2009 cars

### 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 Failure - BCM

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
B+ Terminal D12 X3 | B1325 03, B1517 5A* | B1325 03, B1517 5A* | -- | --
B+ Terminal 11 X1 | B1517 5A | B1517 5A | -- | --
Ground | -- | B1517 5A | -- | --
*The scan tool will not power up from the DLC if the B+ circuit terminal D12 X3 is open or shorted to ground.

### Typical Scan Tool Data

#### Battery Voltage Signal

Circuit | Short to Ground | Open | Short to Voltage
--- | --- | --- | ---
Operating Conditions: Ignition ON, Engine OFF. Parameter Normal Value: 12.60 V
B+ Terminal D12 X3 | 0.00 V* | 0.00 V* | --
*The scan tool will not power up from the DLC if the B+ circuit terminal D12 X3 is open or shorted to ground.

#### Batt. Voltage High Res.

Circuit | Short to Ground | Open | Short to Voltage
--- | --- | --- | ---
Operating Conditions: Ignition ON, Engine OFF. Parameter Normal Value: 12.600 Volts
B+ Terminal 11 X1 | 0.000 V | 0.000 V | --
Ground Terminal 9 X1 | -- | 0.000 V | --

### Circuit/System Description

The body control module (BCM) has 2 circuits for monitoring vehicle system voltage. The circuits are supplied by the IBCM 1 fuse and the BATT SENSE fuse. The BCM monitors the system voltage on the 2 B+ circuits to ensure that the voltage stays within the normal range. Damage to components, and incorrect data may occur when the voltage is out of range.

### Conditions for Running the DTC

The BCM is awake.

### Conditions for Setting the DTC

The voltage of the 2 BCM battery sense circuits differ by 1 V for 10 seconds.

### Action Taken When the DTC Sets

Regulated voltage control (RVC) is disabled.

### Conditions for Clearing the DTC

• | The DTC will pass when the malfunction is no longer present for 10 seconds.

• | A history DTC will clear after 50 consecutive ignition cycles have occurred without a malfunction.

### Diagnostic Aids

A high or low voltage DTC in multiple modules indicates a concern in the charging system.

### Reference Information

#### Schematic Reference

Starting and Charging Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Charging System Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Verification

1. Engine running, accessories OFF, measure and record the battery voltage at the battery terminals. The voltage should be between 12.6-15.0 V.

⇒ | If not within the specified range, refer to Charging System Test.

2. Observe the scan tool Battery Voltage Signal parameter and the Batt. Voltage High Res. parameter. The reading for both parameters should be between 12.6-15.0 V, and should be within 1 V of each other.

### Circuit/System Testing

1. Verify that a test lamp illuminates between the B+ circuit fuses in the BCM listed below and ground.

• | The Ign Sensor fuse

• | The Interior Lights fuse

• | The Door Lock fuse

⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

2. Ignition OFF, disconnect the harness connectors at the BCM.
3. Ignition OFF and scan tool disconnected, open and close the driver door, and wait 45 seconds. Test for less than 5 Ω between the ground circuit terminals listed below and ground.

• | Terminal 9 X1

• | Terminal 12 X1

• | Terminal 13 X2

• | Terminal E12 X4

⇒ | If greater than the specified range, test the ground circuit for an open/high resistance.

4. Verify that a test lamp illuminates between the B+ circuit terminals listed below and ground.

• | Terminal 11 X1

• | Terminal D12 X3

⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

5. If all circuits test normal, replace the BCM.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References - for BCM replacement, setup, and programming.