Overheating
For a quick check, make a jumper and connect them directly to the battery, but only for a moment. If there is a problem, don't keep it connected for more than a split second. You're only testing to see if the fans kick on or not. If they don't, then the issue is the fan motor.
A weak ground can cause heat, which can burn up elect. devices
Question, I am guessing if you had the AC charged, it wasn't working b4, so you didn't notice if the fans were not coming on with AC on?
Do the fans work norm, or throw codes w/o AC
As said, try an wire them direct to test, maybe use a 30 amp fuse-hard to believe 2 fans could be bad
Also make sure the rad. is full, who knows, maybe the shop drained it and didn't get it filled
Question, I am guessing if you had the AC charged, it wasn't working b4, so you didn't notice if the fans were not coming on with AC on?
Do the fans work norm, or throw codes w/o AC
As said, try an wire them direct to test, maybe use a 30 amp fuse-hard to believe 2 fans could be bad
Also make sure the rad. is full, who knows, maybe the shop drained it and didn't get it filled
correct i have not had the a/c running with the current fan that i have on it now. (i changed to a single fan when i installed the procharger). With out the A/C i dont know how to turn the fan on directly??
i checked the rad. when it was over flowing from the reserve cap. The fan could very well be shot but would that make both fan relays throw codes like that? i wouldn't think so but maybe that is the issue I'm having. If that is the case, i don't understand why charging the A/C would automatically make the fan stop working. i know that its going to work a lil harder but who knows.
i checked the rad. when it was over flowing from the reserve cap. The fan could very well be shot but would that make both fan relays throw codes like that? i wouldn't think so but maybe that is the issue I'm having. If that is the case, i don't understand why charging the A/C would automatically make the fan stop working. i know that its going to work a lil harder but who knows.
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From: Barto PA
did ya make sure the wiring is still right for the fans. With a/c a single fan isnt going to cut it by what i read on here. Dont know if you have fmic or the twin intercoolers though.
As far as I know the fan was wired correctly, I took off the stock fans and replaced it with the single procharger fan. (I didn't have a issue for 2 years until i got the A/C charged) and as far as i know i think the single fan should work with a A/C system.
I have twins, So I might need to change to a dual fan set up? why would it kill my relays just by turning it on?
I might just have to take this to my tuning guy to see if he can get the fan to come on, other than that I think I'm just going to be guessing at things it could be.
I have twins, So I might need to change to a dual fan set up? why would it kill my relays just by turning it on?
I might just have to take this to my tuning guy to see if he can get the fan to come on, other than that I think I'm just going to be guessing at things it could be.
So i took the relays from the fan and put it in the starter location and both relays are fine, took the fan wires and hooked them up to the battery direct and fan works. So if anyone has any suggestions i'm all ears.
Last edited by lbm13186; Jul 27, 2015 at 08:43 PM.
So found a lil info from some previous treads... thinking this may be my issue
Found this:
The P0480 code is detected when the Powertrain Control Module (PCM) detects that the commanded state of the driver and the actual state of the control circuit do not match.
So I take it your AC control relay is spliced into the ECU control circtuit to ground your relays. The ECU then sees that it's control wires are grounded although it has not commanded them to ground.
http://engine-codes.com/p0480_chevrolet.html
Hopefully someone has experienced this and knows of a fix. I think you could solve this with another relay for isolation, but there may be an easier solution.
What I did is ran parallel fan relays one each ground triggered 1. by the ecu and 2. by a trinary AC pressure switch to run the fan. This trigger would be analogous to your always on fan state when the AC is turned on.
In this configuration.....
Then the computer doesn't t already "see" ground on the fan relay trigger with the AC on since the relays are parallel with separate wiring to each. I use a small bus bar at the fan shroud to tie the outputs from both relays which drive the fan. Of course at times both relays are hot, but the ecu is never back fed ground so no error code.
Another option would be to use a diode to isolate the computer from the other ground trigger.
Found this:
The P0480 code is detected when the Powertrain Control Module (PCM) detects that the commanded state of the driver and the actual state of the control circuit do not match.
So I take it your AC control relay is spliced into the ECU control circtuit to ground your relays. The ECU then sees that it's control wires are grounded although it has not commanded them to ground.
http://engine-codes.com/p0480_chevrolet.html
Hopefully someone has experienced this and knows of a fix. I think you could solve this with another relay for isolation, but there may be an easier solution.
What I did is ran parallel fan relays one each ground triggered 1. by the ecu and 2. by a trinary AC pressure switch to run the fan. This trigger would be analogous to your always on fan state when the AC is turned on.
In this configuration.....
Then the computer doesn't t already "see" ground on the fan relay trigger with the AC on since the relays are parallel with separate wiring to each. I use a small bus bar at the fan shroud to tie the outputs from both relays which drive the fan. Of course at times both relays are hot, but the ecu is never back fed ground so no error code.
Another option would be to use a diode to isolate the computer from the other ground trigger.
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