Power Supply and References
Capoworks ECU boards normally accept a protected vehicle supply and derive their own processor, I/O, and sensor rails. The exact input connector, fuse or main-relay path, reverse-polarity protection, transient protection, regulator topology, and current budget differ by board and revision. There is no universal input-voltage or current rating to reuse across revisions.
The main relay may switch the ECU's run supply. On some boards firmware controls that relay; on others the relay is handled outside the normal output map. The microRusEFI configuration, for example, documents a battery-sense input fed from the main relay while the relay itself is controlled by its TLE8888. Do not assign a main-relay output merely because a connector has a similar label.
The analog sensor reference is also board hardware. Firmware's adcVcc is a
measurement-conversion scale, not permission to power a sensor from any nearby
pin. Dedicated sensor 5 V supplies may be loaded by several sensors, so use the
board revision's supply limit. Boards that monitor the 5 V rail register a
Sensor5vVoltage channel; the sensor checker reports a fault outside its
implemented window. Header or rail measurements, divider factors, and ADC
channels remain revision-specific.
Keep high-current power returns and sensitive sensor-return paths distinct unless the board schematic explicitly joins them. A good battery-voltage reading does not prove the analog reference or a remote sensor ground is correct. During diagnosis, compare battery voltage, the monitored sensor supply, and raw ADC/divider information for the same channel. If readings move together with load current, investigate the ground or supply path rather than recalibrating the sensor. Consult the Atlas or Universal 112 page only when its identity matches the installed board.