distinguish
The thermistor type water temperature gauge consists of a thermistor type water temperature sensor and a bimetallic plate, as shown in Figure 1. Among them, the thermistor is the sender of water temperature information, and the bimetallic heating wire is the receiver, and the two are connected in series. The water temperature sensor is installed in the waterway and comes into contact with the cooling water. When the water temperature is low, the thermistor value is high, the current in the circuit is small, the heat generation of the resistance wire is small, the bimetallic sheet is slightly bent, and the indicator needle is in the low-temperature zone (Zone C). When the water temperature is high, the thermistor value is small, the current passing through the circuit is large, the heat generation of the resistance wire is large, the bimetallic sheet bends and deforms greatly, and the indicator needle points towards the high temperature zone (H zone).
The water temperature sensor used in the water temperature gauge is a negative temperature coefficient thermistor, which is installed in the cylinder head water jacket. The water temperature gauge uses a water temperature sensor.
1 Thermistor type water temperature gauge
1 thermistor; 2 Information transmission; 3 bimetallic sheets; 4 Indicator needle; 5 Information receiving documents
1 Thermistor; 2 conductive sleeves; 3 conductive springs; Noon copper joint; S-G tube; 6 end buttons; 7 Conductive rod; 8 wires
The water temperature gauge uses a water temperature sensor, with its terminal connected to the water temperature gauge and the other end grounded through the sensor housing.
testing
When the engine water temperature is low, the water temperature sensor on the water temperature gauge inputs water temperature information to the ECU, which enriches the air fuel ratio and stabilizes engine operation. If the water temperature sensor does not display cold engine status information at this time, it will dilute the air fuel ratio and cause abnormal engine operation. Similarly, if a cold engine message is sent after warming up, it will increase the air fuel ratio and cause the engine to malfunction.