No analog input is left for the battery monitor

What ArduPilot says:

• Config Error: No analog voltage channel for battery N
• Config Error: No analog current channel for battery N

New in 4.7. A battery monitor is set to an analog type (BATT_MONITOR 3, 4 or 31) but the board could not give ArduPilot an analog input to read it with. It is a Config Error: the flight controller repeats the message and does not finish starting until the parameter is corrected. The number counts from 0 here: “battery 0” is the first monitor (BATT_MONITOR), “battery 1” the second (BATT2_MONITOR).

What to do, most likely first

1. A second or third monitor was switched on by mistake, or with a type the board cannot serve.

   CheckBATT2_MONITOR and the later ones should be 0 unless that sensor exists.

   FixSet the monitor that is not fitted to 0 and reboot. Parameters can still be changed while the board shows a Config Error.

2. All the board's analog inputs are taken: several analog monitors, an analog airspeed sensor, analog RSSI.

   FixFree an input, or use a digital sensor type for one of the batteries, and reboot.

3. The board has no analog battery input at all.

   CheckThe board's documentation says which battery sensor it carries.

   FixChoose the type of the sensor it does have (INA2xx, DroneCAN, ESC telemetry) and reboot.

Parameters to look at

Where to do it:Setup & Tuning GuideBoard & Wiring Planner