P06B5: Motor B has a separate high sensor-supply diagnosis

The P06B5 row belongs to motor B control electronics. GM identifies the monitored quantity as the scaled 15V sensor supply and rejects a value above 18V. The “B” designation is important: a result from motor A's supply does not establish the condition of the motor B circuit.

Wakeup and sampling affect the observation

Evaluation occurs with the wakeup signal on. The table specifies 100 failing counts out of 150 at approximately 10.4ms per count. An event record should therefore preserve whether the controller was awake and whether the excessive reading persisted through a monitored interval.

A separate five-volt reference-high code, P0653, appears on the same page. Another row addresses the controller's 12V power supply. These are distinct voltage domains; treating all of them as a generic battery-voltage check would lose the monitor's actual target.

Interpret the measured rail before choosing a repair

Record the motor B controller identity and exact voltage parameter alongside other supply faults. If the diagnostic tool exposes only vehicle battery voltage, it has not necessarily exposed the scaled sensor rail used for P06B5.

Nothing in the source establishes whether a regulator, connection or other component failed, and no connector pin assignment is provided. Further investigation requires the matching service procedure. Work around inverter and motor-control equipment should be performed by a trained high-voltage technician using the prescribed de-energization and verification process.

Source and applicability

GM 2010 10OBDG10 Hybrid Diagnostics, only the cited controller and monitor. These are historical calibration examples; individual vehicle, engine and hardware applicability is not established. GM PDF, page 300.