2014 Dodge Dart rad fan stays on
Hello group,I have this 2014 dart cooling fan runs full speed when car is running al the time.scanned for code only code found for AGS performance.that code is there for long time before even this problem started.data shows pcm turning the fan on around 67 %...temp sensor is good,shows normal number.ac request off,ac high side pressure stays 90 psi ,even disconnect ac high pressure sensor.fan still runs the same. I'm try to figure out what Ecm input needs to turn the fan on?car is not overheating ,coolant level is good.is there any other temp sensor that control the fan input?when I reset ecu it stay calm for 10 minutes.temp gauge sits in the middle.could it be a faulty computer or may b an update needs to done?thank you any suggestion ,advice would be appreciated .Stay safe Upkar …
Maybe you can Check the cooling fan rellay and circuit or next step check the body control module. Good luck
Agree with check for stuck closed relay. Simple is good.
Fan control module fault or module not seeing the signal from the ECM the most common with any system with that design. Something like that. BRNVIO pin 3 on the fan control module will have a pulse width modulated signal to control the speed. A fault in the system defaults to high speed to protect the engine from overheating. BTW the AGS should be fixed it may come into play
My first thought without looking at any diagrams at this point is to go into module controlling the fan to come on > using bi directional controls to turn it on then try and turn it off in this case does it turn off when commanded? ( in this case that would tell you computer is OK and capable of turning it on and off when commanded to do so and now the mystery begins what is it seeing to keep…
What does the coolant temp read on the OBD 2 global side?. The temp reading you are seeing on the enhanced side could be a default reading.
Check ac pressure switch pid if available
Has the Engine coolant temp sensor been replaced recently? Maybe replaced with wrong sensor? I read somewhere that vehicles made for Canada get a different ECT than those for US due to extreme cold conditions there.
Remove cooling fan relays and see if any codes are generated? You stated that you can clear code/reset and fans stay off for 10 minutes would suggest that which ever module is in control of fans, maybe sensing an issue.
Yes this has a an control module,
Temp reading changes with temp change,I also swapped relay,ac pid read normal woth ac off around 90 psi at 27c.i need to add when scanned for all module fould no communication with PCM code stored in memory in tcm and bcm,cleare them didn't come back but fan still same..
Go after what actually controls the fan, (the fan control module) and it isn't something that shows up in a scan. You actually have to get the wiring schematics out and test with a scope or a DVOM that is able to display dwell time etc. Get the schematics out and do some testing. This should have been the 1st test after a scan that didn't show a real fault why the fan was running.
First, would you please put a space after the period in your posts. Having all those links in your post makes it hard to read. Second, breaking your post up into paragraphs makes it easier to read as well. This is a pretty basic system, knowing the theory of operation always helps in figuring out what is wrong. The Radiator Fan Module is a smart device which controls the Pulse-Width Modulated…