Temperature Gauge: Description and Operation

With the ignition switch in ON (II) or START (III), voltage is applied through fuse 13 and the fuel and engine coolant temperature gauges. The gauge circuit is grounded at G402.

The Engine Coolant Temperature (ECT) gauge is divided into 7 separate segments. The number of segments that light up depends on the input from the engine coolant temperature (ECT) sending unit. The sending unit's resistance varies from about 142 ohms at low engine temperature to between 49 and 32 ohms at high temperature (radiator fan running).

The fuel gauge is divided into 20 separate segments. The number of segments that light up depends on the input from the fuel gauge sending unit.

The sending unit's resistance varies according to the volume of the fuel in the tank: 239-314 ohms at full, 116-188 ohms with a half tank, and 16-32 ohms at empty.