Battery Sensor Description and Operation

Description

Vehicles have many control units that require a large amount of electricity. These units control their own systems based on information from various sensors. It is important to maintain a stable power supply because these sensors provide a variety of information. The battery sensor is installed on the battery negative (-) terminal. It transmits battery voltage, current and temperature information to the ECM. The ECM controls charging voltage output based on these signals.

When a battery sensor signal fault occurs, check whether the parasitic current draw is abnormal (refer to Inspection).

A new battery sensor requires several hours to correctly determine the battery condition. Perform the following procedure after replacing the battery sensor. 1 Turn the ignition switch ON/OFF. 2 Leave the vehicle in park mode for more than 4 hours. 3 After 4 hours, make sure the battery SOC (State of Charge) is displayed correctly on GDS.

For a vehicle equipped with a battery sensor, be careful not to damage the battery sensor when replacing or recharging the battery. When replacing the battery, it must be the same (type, capacity and brand) as originally installed on your vehicle. If a battery of a different type is installed, the battery sensor may recognize the battery as abnormal. When installing the ground cable to the negative battery terminal, tighten the clamp to the specified torque of 3.9~5.9 N·m lb-in (0.4~0.6 kgf·m, 3.0~4.4 lb-ft). Excessive tightening torque may damage the internal circuit of the printed circuit board and the battery terminal. When charging the battery, ground the negative terminal of the auxiliary battery to the vehicle body.