"Key Battery Low Replace Key Battery" is Displayed on the Multi-information Display [10/2018 - ]: Description
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When driving with an electrical key transmitter sub-assembly that has a low transmitter battery, a transmitter battery depletion warning is displayed on the multi-information display in the combination meter assembly.
The certification ECU (smart key ECU assembly) monitors the transmitter battery of the electrical key transmitter sub-assembly. When the voltage drops, the certification ECU (smart key ECU assembly) sends a display request to the multi-information display via the CAN communication line.