Service Information

Volt

DTC P15F2

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 P15F2: Engine Torque Command Signal Message Counter Incorrect

This diagnostic applies to internal microprocessor integrity conditions within the engine control module (ECM). The hybrid powertrain control module is internal to the power inverter module, often referred to as the drive motor generator power inverter module and is not serviced separately. The hybrid powertrain control module sends an engine torque requested message to the ECM over the serial data circuits. The ECM monitors the data to verify the indicated engine torque requested calculation is correct. The ECM processor monitors the data to verify that the engine torque command is correct.

Conditions for Running the DTC

•	Vehicle is ON.

•	The system voltage is 8-18 V.

•	DTC U1817 is not set.

Conditions for Setting the DTC

The control module has detected an internal malfunction.

Action Taken When the DTC Sets

•	DTC P15F2 is a Type A DTC.

•	The hybrid powertrain control module requests the hybrid powertrain control module 2 to open the high-voltage contactor relays.

Conditions for Clearing the DTC

DTC P15F2 is a Type A DTC.

Reference Information

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Circuit/System Verification

Note: Diagnose and repair any communication DTCs prior to performing this testing.

If the DTC is set, program the K20 ECM. If the DTC resets, replace the K20 ECM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for ECM replacement, programming and set-up.