Hyundai Santa Fe (TM): Charging System / Battery Sensor. Description and operation
Vehicles have many control units that use more electricity. These units control
their own system based on information from various sensors. It is important
to provide a stable power supply as these sensors bring diverse information.
Battery sensor is mounted on battery (-) terminal. It transmits battery voltage,
current, temperature information to ECM. ECM controls generating voltage by
duty cycle based on these signals.

Removal
Battery
1.
Turn the ignition switch OFF and disconnect the battery (-) terminal
(A).
Tightening torque :
7.
Removal
1.
Turn the ignition switch OFF and disconnect the battery (-) terminal.
2.
Disconnect the battery sensor connector (A).
Other information:
Inspection
Self Diagnosis With Scan Tool
It will be able to diagnose defects of SMART KEY system with diagnostic tool
quickly. diagnostic tool can operates actuator forcefully, input/output value
monitoring and self diagnosis.