P0C19: motor A torque performance combines several security checks

P0C19 is motor A torque-delivered performance in the GM document. The source groups several torque-security tests under this code, so the generic title should not be interpreted as a direct measurement proving that the motor mechanically failed to produce torque.

Identify which security check failed

One branch checks the sum of three phase currents against a 75 A threshold with a specified persistence rule. Another compares a calculated checksum with its previously saved value. A further branch monitors whether the SPI rolling count continues to update, using a 90 ms threshold.

These are different types of evidence. A phase-current consistency issue, a stored-data integrity failure and stale torque-command communication should not be collapsed into the same replacement diagnosis.

Controller state changes the other comparisons

Additional branches compare DC-current direction and magnitude with command and speed, or compare calculated and reported torque values. Some require an active power stage; others specifically use the three-phase short or open state. Retain the controller state and any available failure detail when investigating the code.

The monitor table does not identify a single required repair or provide a safe test that an owner can reproduce. Vehicle-specific service information must determine the failed branch and appropriate verification. A trained hybrid technician should evaluate related current and communication faults, establish proper high-voltage precautions for physical work, and confirm the relevant security checks after addressing the cause.

Source and applicability

GM 2010 10OBDG10 Hybrid Diagnostics, cited BPCM or hybrid-controller monitor only. Historical calibration values are not universal specifications; no per-code model, engine or hardware fitment has been established. GM PDF, physical page 292 · GM PDF, physical page 293 · GM PDF, physical page 294.