Somerset Regal L4-151 2.5L (1985)
Engine Sensors - VIN L
1. If the TEMP display is at cool when the engine is warm or hot, there is an open in the sender circuit. Remove the connector from the coolant
temperature sender/switch and short terminal A (DK GRN/WHT) to ground.
a.
If the display now shows full hot, the wiring is good. Install a new coolant temperature sender/switch.
b.
If the display remains at cool, locate and repair the open in the DK GRN/WHT(135) wire.
2. If the TEMP display shows hot when the engine is cool, there is a short in the sender circuit. Remove the connector from the coolant temperature
sender/switch.
a.
If the display now shows cool, the vehicle wiring is good. Install a new coolant temperature sender/switch..
b.
If the display remains at hot with the connector removed, locate and repair the short in the GRN/WHT(135) wire.
3. If the coolant temperature warning indicator is on when the engine is cold or at normal operating temperature, remove the connector from the coolant
temperature sender/switch. Turn the ignition switch to the RUN position.
a.
If the bulb goes out, install a new coolant temperature sender/switch.
b.
If the bulb remains on, locate and repair the short in the DK GRN(35) wire.
