Powertrain Control Module (PCM) Power and Ground Signals: Notes

Vehicle Buffered Power (VBPWR) 

The VBPWR is a PCM-supplied power source that supplies regulated voltage (10 to 14 volts) to vehicle sensors that run off 12 volts but cannot withstand VPWR voltage variations. It is regulated to VPWR minus 1.5 volts and is voltage limited to protect the sensors.