Temperature Gauge: Description and Operation
Battery voltage is supplied to the gauges from the METER fuse in the passenger compartment fuse box when the ignition switch is in ON or START.The coolant temperature gauge pointer is moved by the magnetic field of two coils at right angles to each other. Battery voltage is applied to the "C" coil from the METER fuse. The circuit then divides into two. One path continues through the H coil and then to ground. The other path goes through the variable resistance engine coolant temperature sender and then to ground. When the coolant temperature is high, the resistance of the engine coolant temperature sender is low and less current flows through the "H" coil, pushing the pointer toward "H". When the coolant temperature is low, the resistance of the engine coolant temperature sender is high and more current flows through the "H" coil pushing the pointer toward "C". With two coils operating the pointer, the gauge is not affected by changes in the voltage.