15 chev tahoe coolant fan not going off

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sb38646

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I have a 2015 tahoe ppv converted to civilian. I noticed a while back that my coolant fan was staying in after i cut it off and temp reading of zero. It would stay on exactly 5 min before shutting off. However, i carry a socket wrench with me and when it happens, I disconnect my second battery (ppv’s have 2) and go another week before happens again. I have replaced sensor while it was working properly so it was a week later before I realized it didnt remedy my situation. Ive read through all the forums and YouTube videos that points straight to sensor. , but on my 5th reset post install
 

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I have a 2015 tahoe ppv converted to civilian. I noticed a while back that my coolant fan was staying in after i cut it off and temp reading of zero. It would stay on exactly 5 min before shutting off. However, i carry a socket wrench with me and when it happens, I disconnect my second battery (ppv’s have 2) and go another week before happens again. I have replaced sensor while it was working properly so it was a week later before I realized it didnt remedy my situation. Ive read through all the forums and YouTube videos that points straight to sensor. , but on my 5th reset post install
replaced which sensor?
 

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What brand ECT sensor was used? Recommend GM OE if available.

Inspect the connector and wiring harness carefully at the ECT for pin fitment and contact.

Probably need to look at the data with a scan tool when it happens (could also do this when it doesn't happen, just to get familiar with the readings). Get the engine coolant temp to see if it makes sense based on how warmed up the engine is. If the reading doesn't make sense, you may be looking at another sensor or a wiring problem in the sensor circuit.
 
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sb38646

sb38646

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Ill get it scanned. Whats weird is, if i get in and take the time to turn key to right before it cranks(like checking to see if fuel pump is working) , letting it sit a sec.then crank and let all dash gauges to their thing before putting in gear it seems fine and i dont have to reset battery. Its when i get in a rush and crank and go that the problem reappears.
 
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sb38646

sb38646

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It came from oriellys can’t remember brand. Its all they had.
 
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sb38646

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It does normally do when its cold outside. When i reset battery and truck is still cold, the temp hand moves fwd normally as it warms. If i drive to town before i notice the fan is running louder than normal, i see its pegged out at zero(160 actually ), ill reset battery and bc truck is warm tge temp hand goes straight to normal reading right before or at 210
 
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Odd that it has happened with two different sensors, but it's certainly possible the new sensor is intermittent. However, I would suspect a connector or wiring issue a bit more, but having the scanner reading the ECT real time -- especially when the gauge is not reading correctly -- and wiggling the connector and wiring might help pinpoint it.
 
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sb38646

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in the summer i noticed that while idle air would not blow cold, but get the rpm’s up by putting your foot into it and would freeze u out. This problem started soon after. Could they be related issues ?
 
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sb38646

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Was in for oil change and tire rotation so asked to get it scanned. They did scan for codes but since fans are working properly right now they inly scanned for stored codes. I only had one P2097 which o am not experiencing any o2 sensor issues right now. They suggested trying a new thermostat. Thoughts???
 
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