Honda 37760-P00-003 Switch Assy., Thermo (A-93) (Nippon Thermostat)

The coolant temperature indicator system consists of a temperature gauge mounted in the instrument panel and a coolant temperature sending unit mounted on the engine directly below the distributor. If an overheating indication occurs even when the engine is cold, check the wiring between the dash and the sending unit for a short circuit to ground. If the gauge is inoperative, test the circuit by briefly grounding the wire to the sending unit while the ignition is on (engine not running for safety). If the gauge deflects full scale, replace the sending unit. If the gauge doesn't respond in the test, check for an open circuit in the gauge wiring. If the sending unit must be replaced, simply unscrew it from the engine and quickly install the replacement. Use sealant on the threads. Make sure the engine is cool before removing the defective sending unit. There will be some coolant loss as the unit is removed, so be prepared to catch it. Check the level after the replacement part has been installed.

For models from year 2005 onwards where two ECT sensors are fitted, the second sensor is located at thermostat housing. Starting with, turn the key in the ignition lock cylinder and then turn the engine off; this is because, if you do not do this, the coolant will spill out of the crossover when the ECT sensor is pulled out and consequently, it must be replaced with a new one. Then, unscrew the electrical connector from the ECT sensor and, using a wrench, unscrew the actual sensor, which, it should be pointed out, most deep socket may not fit to. It is necessary to remove the faulty sensor and any time a new sensor is being installed or an old sensor is being put back, it is recommended that a new O-ring be fitted. Lastly, replace the sensor as you would do when using the removal process ensuring that the new one is well fixed.

First of all, remove the engine cover, drain the coolant, disengage the ECT sensor, unscrew it, replace its O-ring, and finally reverse the process to install. Then do the same for 2003-2006 Acura and Honda Models from 2005. For 2007 Acura models with two ECT sensors, lift the vehicle, remove the splash shield, drain coolant, disconnect the sensor, replace the O-ring, and reverse that procedure for installation.

All models use a variety of electronic sensors and an onboard computer to monitor various engine parameters, engine temperature being one of them. The Powertrain Control Module controls the temperature gauge on the instrument cluster. An individual sending unit for the temperature gauge is not necessary with this technology.

Drain the engine coolant, remove the air filter housing, and disconnect the electrical connector from the ECT sensor. Unscrew and remove the ECT sensor and remove and discard the old O-ring. Tighten the ECT sensor to the correct torque, refill the cooling system, raise the vehicle, and support it securely on jackstands. Remove the lower splash shield, unplug the electrical connector, and untighten the sensor from the radiator. To reinstall, switch the removal steps going from the final step to the beginning step. Install a new O-ring on the sensor, tighten the ECT sensor securely, and refill the cooling system.