ASA Electronics iN-Command JRVCS105 Troubleshooting Manual page 12

Above is the Water tank sending unit. The sending unit runs on 7 VDC supplied by the BCM. The 7 VDC
signal runs to a sensor embedded into the side of the water tank. The 1/3, 2/3, and Full sensors are then
aligned in an ascending diagonal line from the 7 VDC sensor. The "To Tank Input" line runs to the BCM
and terminates at Pin s 1-7 depending on the tank. When water or waste starts to fill the tank, it contacts
the 7 VDC sensor and the 1/3, 2/3, and Full sensors. The Voltage travels through the 1/3, 2/3, and Full
sensor leads to a resistor bank, then out the red wire to the BCM. If the BCM is not receiving the correct
voltage (seen on Page 4 BCM Pin Values/Tank Levels in the Notes section) on Pins 1-7, it will not reflect
the correct tank level.
Should the incorrect voltage be coming from the tank, there could be debris on the sensor (for the Gray
and Black tanks) , the line to the 1/3, 2/3, or Full sensors are not terminated correctly, the sensors are
not installed at the desired angle, or the sensor is bad.
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