Low Engine Coolant Indicator

The Low Coolant indicator (amber) will be illuminated in order to indicate to the driver that the engine coolant level is low. The engine coolant level switch is a discrete input to the BCM that will close when the engine coolant is low. The indicator will illuminate under the following conditions:
^ When the input has been active low for at least 10 seconds
^ When the ignition switch is in the ON position

The indicator will be commanded OFF if the switch input goes inactive for at least 2 seconds. This is a distributed function between the BCM and the instrument cluster. The BCM will perform the following functions:
1. Read the status of the engine coolant level switch input
2. Determine the indicator control
3. Send the control state to the instrument cluster via the SPI serial data bus

The instrument cluster will read the low coolant indicator control state in the SPI message and control the indicator directly.