Low Coolant Indicator

The low coolant indicator receives battery voltage with the ignition switch is in the following positions:
^ RUN
^ BULB TEST
^ START

The low coolant indicator turns on when ground is applied to the instrument cluster terminal A15 through circuit 68. Ground is applied by either of the following:
^ The engine coolant level indicator module
^ The BCM

The engine coolant level switch grounds the indicator with the coolant level in the coolant reservoir below the minimum recommended level. The ground is applied at the same time to the BCM at connector C3 terminal D13. The BCM then provides a continuous ground path to the indicator for the remainder of the ignition cycle. This prevents the indicator from turning on and of if the low coolant condition is momentary.

The BCM also turns the low coolant indicator on for approximately 1 second during bulb test.