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Anyone ever seen this problem my coolant fan runs continually and gauge reads hot ,both the light and bar graph ,2017 825i , it does this upon start up when the engine is cold
 

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Check wires and pins at coolant sending unit. . probably a bad sending unit, can remove and test, as your fluid heats up the ohms change.
 

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Be aware there is a temperature switch in the circuit along with a relay. Posting the year of your Gator is useless. JD uses S/N for diagnostics relevance. Also suggest you check for codes as stated in the TM.

If you need more than what is shown below, I suggest you purchase the Technical Manual.


Below is copy and paste from the technical manual for S/N's above 060001.
Theory of Operation - Coolant Temperature Sensor: The coolant temperature sensor contains two thermistors. A thermistor is a semiconductor device having a resistance that decreases rapidly with an increase in temperature. One thermistor is used exclusively by the ECU to control the cooling fan, engine operation, and the coolant temperature warning light. The remaining thermistor is connected to the display panel temperature gauge. Although physically housed in the same sensor, the two thermistors are electrically isolated. Theory of Operation - Cooling Fan: As the coolant temperature approaches 95°C (203ºF), the ECU sends a ground level (“LO”) signal via the 65 and 310 Org wires to the K03 fan relay fan switch input. One side of the fan relay coil has switched battery voltage (V_EL) with the key switch on. The LO signal grounds the opposite end of the coil, energizing the relay. Battery power from the 30A fan fuse flows via the relay contacts and 315 Org wire to the C-22 cooling fan connector. The fan motor is grounded by the 100A Blk wire to the 100-series ground bus. Cooling fan operation continues until the engine temperature drops below 88ºC (190ºF)

Theory of Operation - Coolant Temperature Light: When the ECU senses that the coolant temperature exceeds 115ºC (239ºF), it sends a LO signal to the display panel via the 64 Org and 305 Pnk wires. This signal allows the display panel to illuminate and flash the coolant temperature warning light. The temperature warning light continues to flash until the engine temperature drops below 110ºC (230ºF). NOTE: Whenever the light is illuminated, the ECU will go into “limp home mode” to protect the engine. Reduced performance will result. Theory of Operation - Temperature Gauge: The temperature gauge is an LCD bar graph display that receives an analog signal from the temperature sensor via the 090 Red and 300 Org wires. This circuit works independently from fan and temperature light operation. The variable resistance from the coolant temperature sensor is processed within the display panel by an analog-to-digital (A/D) converter. The resultant digital signal is then used to operate the temperature gauge bar graph.

Cooling Circuit Electrical Diagnosis (SN 060001-) Service ADVISOR and/or OBD code is required for diagnosing this system. Also, see fuel injection section for detailed information. The only components that can be tested in these circuits are electromechanical, such as the fan and relay.
 

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Discussion Starter #4
Anyone ever seen this problem my coolant fan runs continually and gauge reads hot ,both the light and bar graph ,2017 825i , it does this upon start up when the engine is cold
Found the problem the coolant temp sensor was bad, when it was being taken out it broke off in the head and was corroded internally, replaced unit all is good now , additional note Gator was a crank no start or very very hard to start when sensor was bad
 

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Thanks for reporting back your findings.

It adds to the quality of the forum when OP's take the time to communicate root or final action taken... Even if no action at all.
 
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