Cooling fan not working
12-03-2013, 10:16 PM
#21
2nd Gear
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Help with cooling fan problem
engine has a temperature sensor in it. It sends info to the computer and then it in turn sends a signal to the fan control module that powers up the fan. The temp gauge working would leave me to believe the sensor is working correctly and i doubt there is an issue with the computer. 2 possible common issues are the fan module or the fan itself.
A little technical to check the module but basically it has 5 wires, ground (black) , power (red) , one wire going to the computer (red/orange) , 2 wires going to the fan (red & Black) so check those and that shoudl help you diagnose it.
More then likely if the fan spins freely by hand its ok (usually when a fan goes out it locks up the fan) BUT the fan going bad can easily short out the module as well. so just slapping in a module may not do it. good luck, paul
A little technical to check the module but basically it has 5 wires, ground (black) , power (red) , one wire going to the computer (red/orange) , 2 wires going to the fan (red & Black) so check those and that shoudl help you diagnose it.
More then likely if the fan spins freely by hand its ok (usually when a fan goes out it locks up the fan) BUT the fan going bad can easily short out the module as well. so just slapping in a module may not do it. good luck, paul
06-07-2015, 09:36 AM
#23
Advanced
Ok guys I need help! I have a 05 vette and the fan does not work. If I turn the ac on then it does work but no ac then no worky. The car will go up to 240 before I turn it off. I put a scanner on it and the temp is right. The computer is not commanding the fan on. If I go under the car and add ground to the signal wire the fan will run. Its like it lost a ground from the computer. I checked the wire from the computer to the module. I replaced the module. If I add power to the fan motor with my power probe the fan works. It gets better, if the car is 240 and I turn the car off the fan will run to cool the car down but if I turn the car back on fan stops. The fan connecter's all look brand new. Any help would be great and basically im down to the computer. Is this something that goes bad! PLEASE HELP!!!!!!!!!!!!!!!!!!!!!!!!!
I have a 2007 with the same symptoms. I have a Predator tool that allows me to adjust the fan tables and see if the ECM is sending the signal to the fan to turn on. According to the scan tool, the ECM is not delivering the request to turn on the fan. The plug is in like new condition, the Fan control module is getting power and the fan itself works when hotwired.
How did you resolve your problem? it sounds like you and I had the same issues.
06-08-2015, 09:20 AM
#25
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I have a 2007 with the same symptoms. I have a Predator tool that allows me to adjust the fan tables and see if the ECM is sending the signal to the fan to turn on. According to the scan tool, the ECM is not delivering the request to turn on the fan. The plug is in like new condition, the Fan control module is getting power and the fan itself works when hotwired.
How did you resolve your problem? it sounds like you and I had the same issues.
How did you resolve your problem? it sounds like you and I had the same issues.
06-08-2015, 09:37 AM
#26
Advanced
So reflashed the diablo tune and adjust the fan tables AGAIN and it seemed to work just fine. I will know later this week when the weather cooperates as to whether the fix worked long term or not.
What did the new ECU, install and flash cost you? I'm curious just in case this doesnt work and I end up going down that route. All the connectors are in excellent shape.
What temp sensor are you talking about? the one that send the info to the DIC? I wouldn't know how to verify its working without buying a new sensor and seeing if they read the same. The car only has 36k miles on it.
09-25-2015, 03:25 PM
#27
Instructor
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Cooling fan notwirking
hi, have kind of same issue. What is wrong with my 06 Z06 is that the cooling fan plug which has at here prong setup show the center prong is burnt out. Fabricated the middle burnt prong and now it works. However,I am going to replace the entire plug and perhaps the fan. Set up.
Last edited by STEEDA0011; 09-25-2015 at 03:39 PM. Reason: Spelling
09-25-2015, 07:38 PM
#28
Safety Car
the melted connector gig of course needs replaced with a new connector but that's just a symptom of the original "disease' the motor is just pulling too many amps thru it and causing these type issues (of course a hot wire to your fan shorting to ground would do it to but that's highly unlikely unless someone has been working around that area and screwed up a wire)
Ya really need a good wiring diagram and a scanner to diagnose the issue properly if its "NOT" a burnt up connector because the fan is pulling too many amps (fan pulling too many amps is why the connector gets like that). With it you can see temp sensor values and whether the computer is calling for the fan on.
One thing I would HIGHLY recommend ""NOT"" using on your vette in circuits like this is a power probe. Very easy to freak out a computer using one of those babies. If you ever need to power something up please get a wiring diagram and make sure you know exactly what you are doing.
The "drivers" in the computer (whether its an injector driver, fan control, fuel pump control etc...) are mostly "ground" controlled and powering one of those up 9 times out of ten will fry that circuit in the computer and since there are not serviceable basically you will be buying a computer so please please please don't use a power probe on your vette. I was an ASE certified master tech for 20 years and never used one for those reasons and because air bag circuits are very touchy and easy to pop a bag in a heart beat. I cant tell you how many cars I worked on with computers and air bags ruined because of guys powering up the wrong wire via a power probe or just a simple hot wire to the battery. If you don't have a wiring diagram and are not 100% sure what circuit and wire yo uare messing with the ndont mess with it. Just some food for thot to help guys save a lot of money and frustration down the line. paul
Ya really need a good wiring diagram and a scanner to diagnose the issue properly if its "NOT" a burnt up connector because the fan is pulling too many amps (fan pulling too many amps is why the connector gets like that). With it you can see temp sensor values and whether the computer is calling for the fan on.
One thing I would HIGHLY recommend ""NOT"" using on your vette in circuits like this is a power probe. Very easy to freak out a computer using one of those babies. If you ever need to power something up please get a wiring diagram and make sure you know exactly what you are doing.
The "drivers" in the computer (whether its an injector driver, fan control, fuel pump control etc...) are mostly "ground" controlled and powering one of those up 9 times out of ten will fry that circuit in the computer and since there are not serviceable basically you will be buying a computer so please please please don't use a power probe on your vette. I was an ASE certified master tech for 20 years and never used one for those reasons and because air bag circuits are very touchy and easy to pop a bag in a heart beat. I cant tell you how many cars I worked on with computers and air bags ruined because of guys powering up the wrong wire via a power probe or just a simple hot wire to the battery. If you don't have a wiring diagram and are not 100% sure what circuit and wire yo uare messing with the ndont mess with it. Just some food for thot to help guys save a lot of money and frustration down the line. paul
