P06B2: Motor A sensor power is a 15-volt rail in this implementation

P06B2 monitors the motor A controller's sensor power supply in this GM hybrid implementation. The source explicitly describes a nominal 15V supply, with a high-fault boundary above 18V. It is therefore different from the five-volt reference circuit listed nearby.

Keep the supply rails separate

P0643 on the same page monitors a five-volt reference above 5.20V, whereas P06B2 monitors the scaled 15V supply. A satisfactory five-volt measurement cannot establish that the supply associated with P06B2 is satisfactory. Equally, an 18V threshold here is not a universal specification for every vehicle using this generic code.

The monitor is enabled when the wakeup signal is on. Its recorded decision uses 100 failing counts within a 150-count window at approximately 10.4ms intervals. A supply trace and wakeup state are more informative than an isolated value obtained while the controller is inactive.

Use controller identity in the handoff

Save motor A module identification, the affected supply parameter and any accompanying reference-voltage or controller-power codes. They distinguish different internal or external supply domains, although this table alone does not locate a physical failure.

The document supplies no approved test point or safe inverter access method. High-voltage equipment remains a professional service boundary even when a monitored internal rail is described as 15V. Use the correct isolation and diagnostic procedure rather than probing an energized power-electronics assembly.

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 288.