• | 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. |
The body control module (BCM) monitors the state of charge (SOC) of the electrical system. If the BCM senses that the SOC at key-on is 30 percent lower than what it was when the engine was running, DTC B1527 will set.
The ignition is ON.
The SOC at key-on is 30 percent lower than when the engine was running and battery drain is more than 2 amps.
There is no battery telltale illuminated or DIC message displayed.
• | The DTC will pass when the SOC is greater than or equal to 80 percent. |
• | The DTC will clear if the fault does not return after 50 consecutive ignition cycles. |
Starting and Charging Schematics
Charging System Description and Operation
Control Module References for scan tool information
Ignition ON, compare the scan tool BCM Prev. State of Charge and Start Up State of Charge parameters. The readings should not differ by more than 30%.
⇒ | If the readings differ by more than 30%, refer to Battery Electrical Drain/Parasitic Load Test. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.