Temperature Gauge

Disconnect terminal from temperature sending unit on engine. Connect one test lead of suitable tester (C-3826) to terminal and other lead to a good ground. Turn ignition on. Turn tester knob to "L". Temperature gauge should show "C" plus or minus 1/8". Turn tester knob to "M" position, pointer should advance to the driving range left of the 1/2 position of dial. Turn tester knob to "H", gauge pointer should move to "H" position on dial. Should gauge respond to the above tests, but does not operate properly when connected to sending unit, indications are of defective sending unit.