Instrument Panel, Gauges and Warning Indicators: Description and Operation

Gauges and Indicators

How the Circuit Works

The gauges and indicators are part of the multiplex integrated control system. Some indicators are controlled by conditions in their specific systems. Information for these indicators is communicated from control unit to control unit across multiplex communication lines. The following indicators are communicated to the gauge control module through the multiplex integrated control system:
- ABS Indicator
- Charging System Indicator
- Fog Light Indicator
- High Beam Indicator
- Lights On Indicator
- MIL Indicator
- Seat Belt Reminder Indicator
- VSA Activation Indicator
- VSA Indicator

Refer to each individual system for more information.

Engine Coolant Temperature Gauge
The engine coolant temperature gauge is controlled by the CPU/fail safe circuit/CAN controller built-into the gauge control module. The CPU/fail safe circuit/CAN controller receives engine coolant temperature information from the ECM/PCM through the fast controller area network transceiver via the multiplex integrated control system. The ECM/PCM receives engine coolant temperature information from the ECT sensor.

Fuel Gauge and Low Fuel Indicator

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 are controlled by the CPU/fail safe circuit/CAN controller built-into the gauge control module. The CPU/fail safe circuit/CAN controller receives fuel level information from the fuel gauge sending unit. The resistance through the fuel gauge sending unit will change according to the level of the fuel within the fuel tank. This varying resistance enables the CPU/fail safe circuit/CAN controller to determine the level of the fuel. When it is determined that the fuel level is low, the low fuel indicator is illuminated. When the ignition switch is turned to LOCK (0), the gauge returns to the bottom of the gauge dial regardless of the fuel level.

Speedometer
The speedometer is controlled by the CPU/fail safe circuit/CAN controller built-into the gauge control module. The CPU/fail safe circuit/CAN controller receives vehicle speed information from the ECM/PCM through the fast controller area network transceiver via the multiplex integrated control system. The ECM/PCM receives vehicle speed information from the output shaft (countershaft) speed sensor.

Tachometer
The tachometer is controlled by the CPU/fail safe circuit/CAN controller built-into the gauge control module. The CPU/fail safe circuit/CAN controller receives engine speed information from the ECM/PCM through the fast controller area network transceiver via the multiplex integrated control system. The ECM/PCM receives engine speed information from the CKP sensors.