DC Power Conversion Test
DC Power Conversion Test
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
Circuit/System Description
The generator control module also called the starter generator control module is comprised of the following three control modules; the hybrid powertrain control module, 14 volt power module and the drive motor control module. These three control modules are non serviceable and are part of the generator control module.
The 14 volt power module supplies the energy that flows between the high voltage (115V) direct current (DC) and low voltage (14V) DC to charge the 12V battery and power accessories. The 14V power module receives a wake-up signal from the hybrid powertrain control module when the ignition is switched to On. After a successful initialization, the 14V power module receives an enable command from the hybrid powertrain control module to begin power conversion.
Diagnostic Aids
A poor connection at the B+ terminal of the 14V power module or open 300 Amp Mega-Fuse in the engine compartment, will prevent the 14V power module from operating.
Reference Information
Schematic Reference
Hybrid Controls Schematics Hybrid Controls Schematics
Connector End View Reference
Component Connector End Views Connector End Views By Name
Description and Operation
Generator Control Module Description and Operation Generator Control Module Description and Operation
Electrical Information Reference
* Circuit Testing Circuit Testing
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Circuit/System Verification
1. Ignition OFF, measure and record the battery voltage at the C1 12V battery terminals. The battery voltage should stabilize between 12.4 and 12.8 V within a few minutes of turning the ignition OFF.
• If not within the specified range, refer to Battery Inspection/Test Battery Inspection/Test
2. Start and idle the engine, accessories OFF, measure and record the battery voltage at the battery terminals. The voltage should be at least 1 V greater than the voltage measured in step 1 but less than 15 V.
• If not within the specified range, refer to Circuit/System Testing.
Circuit/System Testing
1. Ignition ON, verify that no K1 14V power module or B18 battery current sensor DTCs are set that would cause a charging system concern.
• If DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.
2. Ignition OFF, measure the voltage across the battery terminals. The voltage should read 12.4 V or greater at room temperature.
• If not within the specified range, refer to Battery Inspection/Test Battery Inspection/Test
3. Connect a carbon pile tester to the C1 battery.
4. Start and idle the engine, turn all accessories off. Observe the voltage reading on the tester. The voltage should read between 12.6-15.5V.
5. Adjust the carbon pile tester so that the 12V current on the 14V power module data list is reading 120 amps. The voltage reading should remain between 12.6-15.5V.
• If not within the specified value, replace the K1 14V power module.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
Control Module References Programming and Relearning for Generator Control Module replacement, programming, and setup for 14 Volt Power Module replacement.