Cooling fan wiring, diaphragm to fuses 5.0

1994Gtmustang

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I understand is two fuses that control. Our cooling fans on a 94 through 1995 Ford Mustang GT I have power going to the 60 amp fuse but no power going to the 10amp fuse.
 

dcm0123

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diagram and fuses

I see where it states there is a 10 amp fuse for the low speed fan but I also see in the relay schematic both low and high speed are fed by the same 60A fuse, not a 10 amp.

The relays in the Fan Module are undersized and overheat then burn out.
 

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1994Gtmustang

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correct I mentioned the relays in the CCRM earlier. Relays are known to go bad after time.
Everyone is absolutely correct the relays are in CCRM There’s also a 60 amp fuse, and a 10 amp fuse that works in conjunction with the CCRM this is the problem, at least for my car. Everything is new there is still no power going to the 10 amp fuse. I’ve traced everything down. The problem is the PCM the computer that one circuit board that controls the 10 amp fuse to send power to it, or to recognize power and grounding points is bad, so what I did was got rid of the factory fan took a fan out of a 2004 Ford mustang GT only ground in power. It sucks that I have to monitor the temperature by the switch inside my car now to cut the fan on but it is OK for now. It is not my daily driver .
 

dcm0123

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Here is a view showing the 10 amp fuse is actually a power seat fuse. Not sure which is correct.
Do you have a problem with your fan?
Also check the connector which plugs into the fan motor. If it is shows signs of excessive heat, it may be bad.

1667760515139.png
 
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1994Gtmustang

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Here is a view showing the 10 amp fuse is actually a power seat fuse. Not sure which is correct.
Do you have a problem with your fan?
Also check the connector which plugs into the fan motor. If it is shows signs of excessive heat, it correct
 
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1994Gtmustang

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Correct the 10am fuse has no power going to it at all. Also, there’s no power going to the coolant temperature sensor plug. To my understanding the coolant temperature plug gets power on the 10 amp fuse. Nothing now when I unplug the coolant temperature plug, I guess to see CCRM makes the fan automatically comes on.
 

dcm0123

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Coolant temp sensor is connected to the computer, not a power source. It has the same connection the other sensors have. The engine would likely not run if there was a problem with this circuit.

The coolant temperature sensor tells the computer the engine is running hot. The computer then tells the Constant Control Relay Module (body control module) to energize the relay which turns the cooling fan on.

 

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1994Gtmustang

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Coolant temp sensor is connected to the computer, not a power source. It has the same connection the other sensors have. The engine would likely not run if there was a problem with this circuit.

The coolant temperature sensor tells the computer the engine is running hot. The computer then tells the Constant Control Relay Module (body control module) to energize the relay which turns the cooling fan on.

Ok but it doesn’t explain why the 10amp fuse has no power and yes the fuse is new both 60amp and 10 amp so what else powers the 10amp fuse because remember even at the coolant temp plug there’s no power either
 

dcm0123

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Depending on how the sensing system was designed, it may not have 12V+ on the temperature sensor plug.
Try unplugging it while the car is running. Th engine may shut off and demonstrate to you the system is working.

Considering the fuse box diagrams do not agree with each other, I have no clue what the 10amp fuse is for. One says power seats, the other says engine fan. Unless you find someone with a Ford OEM manual, you may never know.
 

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All the temp sensors in the car use something called a thermistor. All it is, is a resistor that changes resistance with temp so all there might be a small voltage on the wire but it is really just testing for the resistance of the sensor.
 

from6to8

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I understand is two fuses that control. Our cooling fans on a 94 through 1995 Ford Mustang GT I have power going to the 60 amp fuse but no power going to the 10amp fuse.
So what did you figure out I'm having the same issue. My low speed fan is not coming on so I wanted to check the fan connectors and I was reading where the middle wire is the ground so I jumped the outside wire and the middle wire and the fan came on I actually think it was the low speed fan that came on. So when I jump over to the other outside wire which one is supposed to be for low speed and one for high speed, there was nothing to fan did not move. That's when I proceeded to check the fuses at the high current fuse panel and the 60 amp for the high speed fan has power there but not the 10 amp
 

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All the temp sensors in the car use something called a thermistor. All it is, is a resistor that changes resistance with temp so all there might be a small voltage on the wire but it is really just testing for the resistance of the sensor.
I wonder why when I tested the fan plug today cuz I was reading up that the middle wire is the ground so I one of the outside wires in the middle wire I tested that jumper it to the battery and the fan came on I believe the low speed. Jumper the other outside wire and I got nothing, the fan did nothing
 

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