John Deere – 1023E, 1025R and 1026R – Coolant Temperature Sensor Test

[1] – Park machine safely.

[2] – Allow engine to cool before servicing the cooling system.

[3] – Remove coolant temperature sensor. (See Remove and Install Coolant Temperature Sensor in Section 20, Group 10.)

[4] –

Suspend sensor (A) in water and coolant mixture.

[5] – Bring water and coolant mixture to specified temperatures while measuring resistance of sensor. Use ohmmeter to check resistance across solenoid terminals.

[6] – If resistance does not meet specification, replace coolant temperature sensor.

[7] – Install sensor.
a. Replace copper washer.
b. Tighten sensor to specification.

c. Refill radiator and recovery tank with approved coolant.