Base (Without Gages)

Fuel Display

The Fuel Gage Sender provides a signal to the cluster that is related to fuel level. With a full tank the resistance is 90 ohms, and with an empty tank the resistance is less than 1 ohm. The microprocessor converts this signal and activates the Vacuum Fluorescent Display. When the bar graph Fuel Display changes from two segments to one, the low fuel symbol in the Fuel Display will light. At the transition from 1 segment to 0 segments, the Low Fuel symbol will flash.

OIL Pressure Indicator

The Oil Pressure Indicator comes on to warn the driver when the engine oil pressure is low. Battery voltage is applied to one side of the bulb. A ground path is provided by the Oil Pressure Switch. It closes when the oil pressure is below 27 kPa (4 PSI) and the Indicator bulb lights. After the engine starts and normal oil pressure builds up, the Oil Pressure Switch opens. The Oil Pressure Indicator goes out.

Coolant TEMP Indicator

The Coolant TEMP Indicator warns the driver of a high coolant temperature. With the Ignition Switch in RUN, BULB TEST or START, voltage from Fuse 11 is applied to the Coolant TEMP Indicator. The bulb is grounded through the Coolant Temperature Switch. The switch closes when the coolant temperature exceeds 258°F (126°C). The bulb lights.

Speedometer and Odometer

The Vehicle Speed Sensor (VSS) generates a signal that indicates the speed of the vehicle. The signal is processed by the Solid State ECM to supply inputs to the Cruise Control Module, the Speedometer and the Odometer.

The Vehicle Speed Sensor is mounted in the transaxle. A magnet rotates near a coil, producing voltage pulses in the coil. The frequency of the AC voltage coming from this coil depends on the vehicle speed. As the speed increases, so does the number of voltage pulses per second.

The ECM takes the voltage pulses from the sensor and uses them to close a Solid State output switch. The output terminal is switched to ground at a rate that is proportional to the speed of the car. The Speedometer and Odometer are switched at the same frequency that the sensor generates, 4000 pulses per mile.

The Speedometer and the Odometer are operated by a circuit board in the cluster. This circuit board converts the pulses received from the ECM into a control signal for the Vacuum Fluorescent Displays.