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 B1527: High Parasitic Load Detected - 12 V BatteryCircuit/System Description
The body control module (BCM) monitors the state of charge (SOC) of the 12 V battery. 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.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
The SOC at key-on is 30 percent lower than when the engine was running and 12 V battery drain is more than 2 amps.
Action Taken When the DTC Sets
There is no battery telltale illuminated or DIC message displayed.
Conditions for Clearing the DTC
| • | 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. |
Reference Information
Schematic Reference
Starting and Charging Schematics
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
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. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
