Fuel Gauge Sender: Description and Operation

How the Circuit Works

The indicators are controlled by relative conditions in their associated systems. For the following indicators the information supplied to the gauge assembly is received via the multiplex control unit:
- Charging System
- Door/Hatch Indicator Light
- Maintenance Required Indicator
- Seat Belt Reminder

Fuel Gauge and Low Fuel Indicator Light

WARNING: Do not smoke while working on the fuel system. Keep open flame away from the work area. Drain fuel only into an approved container.

The fuel gauge and low fuel indicator light are controlled by the CPU built-in the gauge assembly. The CPU receives fuel level information from the fuel gauge sending unit.

The fuel gauge sending unit's resistance varies from about 11 - 13 ohms at full to about 130 - 132 ohms at empty. The fuel level signals current changes with the varying resistance, which enables the CPU to determine the level of the fuel. When the CPU determines that the fuel level is low, it turns the low fuel indicator light on. When you turn the ignition switch to LOCK (0), the gauge returns to the bottom of the gauge dial regardless of the fuel level.