Low Fuel Lamp/Indicator: Description and Operation

Electronic Instrument Cluster:

Instrument Cluster Legend:

Sensor Locations - Typical:

The low coolant indicator comes on to warn the driver when low level of coolant exists in the radiator. Battery voltage is applies to the low coolant module. When a low coolant condition exists, a signal is sent to the low coolant module from the low coolant probe. The low coolant module will provide a ground for the low coolant indicator which lights to warn of low coolant in the radiator.

The low coolant probe is not a switch that opens or closes. It has a very high resistance to ground (more than 50,000 ohms) when the engine coolant level is low. This causes the low coolant module to light the low coolant indicator. With more of the probe covered by coolant, its resistance decreases. When the fluid level is good, the resistance will be less than 10,000 ohms. At 50,000 ohms, the probe is partly covered and the fluid is not low enough to cause the warning to be displayed.