how to install transmission temperature gauge on ranger

If you do not get a reading, check any fuse labeled “Engine,” “ECM” or “PCM.” If all fuses are good, trace that wire back to the computer and repair any damage to the wire. Proceed to the next step, if you receive a voltage reading. You should see 5 or 12 volts with the ignition key in the “On” position, depending on how your vehicle is designed. Touch the positive lead from your meter to the reference supply wire. Connect the negative lead of the multimeter to a good ground - ideally the negative battery terminal or one of the body-to-engine grounds. Set your multimeter to read DC volts, on the 20-volt scale. Review your repair manual to determine which wire supplies the reference voltage. It is commonly found threaded into the engine block, thermostat housing, cylinder head or upper intake manifold.Ĭheck for reference voltage to the sensor.ĭisconnect the wiring harness from the sensor. The location of the sensor varies depending on what year, make and model of vehicle you are working on. The following procedure will work for most vehicles, but check the repair manual for a description of the sensor’s operation before you begin. Removal of other components may be necessary to access the coolant temperature sensor, the sensors wiring or the wiring for the temperature gauge. You will need to drain and fill the cooling system as well as test specifically colored wires. You should have a service or repair manual written for your specific vehicle prior to attempting these tests. To diagnose an inoperative temperature gauge, you’ll need to test the coolant temperature sensor and the wiring for that circuit. Depending on how your vehicle is designed, that modified voltage travels directly to the temperature gauge - more common on cars built before 1996 - or back to the car’s computer, which then controls the temperature gauge in the instrument cluster. At low engine temperatures, almost all of the reference voltage is dropped as the current passes through the sensor, and when the engine is warmer, very little voltage is dropped. On most vehicles, the resistance of the sensor decreases as the temperature increases. As the coolant temperature rises or falls, the resistance of the sensor changes as well. This sensor is nothing more than a thermistor - a variable resistor that changes resistance with temperature changes. The temperature gauge reading starts out as a reference voltage that is sent to the coolant temperature sensor.

How to install transmission temperature gauge on ranger