HELP: Radiator Fan Wiring/Fans Continue To Run -PICS-
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HELP: Radiator Fan Wiring/Fans Continue To Run -PICS-
Hey guys, ok here's the deal bought a FRC that I knew had some shotty wiring located by the battery box. It seems to be the radiator fan relay, but the harness has been cut (PICS) and re-wired...
The radiator looks to have been replaced at some point and I assume this is when the bad wiring was done. Here's what I know:
-The GRAY wires from the relay are connected to the WHITE wires which run to the radiator.
-The green wire which is cut, when touched the positive terminal will power the fans
-Can someone explain what it is I'm looking at for certain?
-Can someone explain where this relay is SUPPOSED to be?
-Can someone tell me what the cut wires are for, and if they are important?
-Can anyone tell me how I should PROPERLY wire this thing lol?
Now, the radiator fans will continue to run (5 mins or so) EVEN AFTER the car is shutoff. Any idea what is causing this and how to fix it?
The car has a mail order Frost tune, could the fans stay on due to the tune programming?
Vehicle:
1999 FRC, Cam, Exhaust, Intake, WITHOUT dual climate control AC
The radiator looks to have been replaced at some point and I assume this is when the bad wiring was done. Here's what I know:
-The GRAY wires from the relay are connected to the WHITE wires which run to the radiator.
-The green wire which is cut, when touched the positive terminal will power the fans
-Can someone explain what it is I'm looking at for certain?
-Can someone explain where this relay is SUPPOSED to be?
-Can someone tell me what the cut wires are for, and if they are important?
-Can anyone tell me how I should PROPERLY wire this thing lol?
Now, the radiator fans will continue to run (5 mins or so) EVEN AFTER the car is shutoff. Any idea what is causing this and how to fix it?
The car has a mail order Frost tune, could the fans stay on due to the tune programming?
Vehicle:
1999 FRC, Cam, Exhaust, Intake, WITHOUT dual climate control AC
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It's some kind of add-on fan controller. People hack crap like that into their car because they're too cheap to tune the computer and adjust the fan temps in it. The gray wires look to run to a temperature probe and that would be why the fans run after you shut it off. I would just pull that thing out and connect the wires back up stock. You should be able to see the ends of the stock wires and where they would reconnect together without that module being wired in there. The stock fan relays and fuses are all in the under hood fuse center. Check the label on the cover and make sure the fuses and relays are still in the box. There should be 3 fuses and 3 relays to run the fans.
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It's some kind of add-on fan controller. People hack crap like that into their car because they're too cheap to tune the computer and adjust the fan temps in it. The gray wires look to run to a temperature probe and that would be why the fans run after you shut it off. I would just pull that thing out and connect the wires back up stock. You should be able to see the ends of the stock wires and where they would reconnect together without that module being wired in there. The stock fan relays and fuses are all in the under hood fuse center. Check the label on the cover and make sure the fuses and relays are still in the box. There should be 3 fuses and 3 relays to run the fans.
Like you said, I REALLY want to yank all of that garbage out because it looks like crap, I just don't know how to replace it properly. I know there's a C6 fan relay kit out there, and I've been trying to see if that would be a suitable replacement...?
Anyone have any idea what the blue wire would be for? I unbolted the fuse box and saw that it was spliced into a factory blue wire that runs into the wire bundle underneath the fuse box.
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Here is the cooling fans wiring schematic:
Wire colors are as noted.
Factory operation is the fans come on at low speed (both fans) when coolant reaches 226 degrees and go off when coolant drops to 219 degrees. If the coolant reaches 235 degrees the fans go to high speed mode (both fans). High speed reverts back to low speed when coolant temp drops to 226 degrees.
You can force low speed operation by turning on the AC. When coolant reaches 185 degrees with AC on the fans start in low speed mode. They do not go to high speed mode unless the coolant reaches 235 degrees.
If the vehicle speed exceeds 35mph then fans are commanded OFF by the PCM no matter what the coolant temp is.
Wire colors are as noted.
Factory operation is the fans come on at low speed (both fans) when coolant reaches 226 degrees and go off when coolant drops to 219 degrees. If the coolant reaches 235 degrees the fans go to high speed mode (both fans). High speed reverts back to low speed when coolant temp drops to 226 degrees.
You can force low speed operation by turning on the AC. When coolant reaches 185 degrees with AC on the fans start in low speed mode. They do not go to high speed mode unless the coolant reaches 235 degrees.
If the vehicle speed exceeds 35mph then fans are commanded OFF by the PCM no matter what the coolant temp is.
Here's what I know about that Relay:
Looks like its a stock relocated relay, but I could be wrong.
Red + Yellow wires are spliced into a single wire with a 10a fuse, and run to a positive terminal so it must be a power supply.
Black wire is run to a factory ground on the firewall
Two Gray wires are spliced into the white wires which run to the radiator
Green is cut, but when touched to the positive terminal will turn the radiator fans on
Orange is cut, function unknown.
Blue is spliced to another blue wire coming from the fuse box
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The blue might be cut into the wire that normally goes to the PCM to turn the fans on high speed. If the blue wire in the original harness is cut then it's likely the end coming from the fuse center so try looking for the other end which would be coming from the PCM.