help with a check engine light
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From: las vegas nevada
help with a check engine light
I have a 2001 vert s/c the check engine light came on a week or so ago went to autozone to have them run the code. apparently it is the Cooling Fan Relay 1 Control Circuit what and where is this and how hard is it to fix thanks
Last edited by shimmy; Feb 23, 2010 at 04:36 PM. Reason: found the right name
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From: Dyer, IN
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St. Jude Donor '03
There are 2 codes that could cause this. P0480, and P0481.
Depending on which you are getting would narrow it down to which specific circuit is the problem.
P0480 is for Fan1, or the low speed fan operation relay control circuit.
First thing to check would be fuse # 49 (30a) in the fuse panel under the hood. Next thing would be to replace the relay (relay # 45 in the fuse panel under the hood).
P0481 is for Fan2, the high speed fan relay control circuit.
First thing to check here would be fuse #14 (10a). If found to be fine, then you have 2 relays to deal with, either of which could be at fault, relay #43, and relay #44.
If fuses and relays are all found to be fine, then the problem becomes a bit more complex to troubleshoot, but chances are good it's one of the above.
Depending on which you are getting would narrow it down to which specific circuit is the problem.
P0480 is for Fan1, or the low speed fan operation relay control circuit.
First thing to check would be fuse # 49 (30a) in the fuse panel under the hood. Next thing would be to replace the relay (relay # 45 in the fuse panel under the hood).
P0481 is for Fan2, the high speed fan relay control circuit.
First thing to check here would be fuse #14 (10a). If found to be fine, then you have 2 relays to deal with, either of which could be at fault, relay #43, and relay #44.
If fuses and relays are all found to be fine, then the problem becomes a bit more complex to troubleshoot, but chances are good it's one of the above.
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St. Jude Donor '03
Not getting your wording there....A fuse "should" be shorted. (ie; continuity between the 2 tabs).
When a fuse blows, it internally separates, breaking continuity and disconnecting power from the circuit.
When a fuse blows, it internally separates, breaking continuity and disconnecting power from the circuit.
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Thread Starter
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From: las vegas nevada
I meant the fuse was blown sorry I am not all their today Im just trying to make sure I dont have a bigger problem then just a blown fuse
and thanks everyone for the help so far
and thanks everyone for the help so far
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St. Jude Donor '03
Start by replacing the fuse. Run the car up to temp until the point the fans should come on (226F on an 01).
If they do turn on and run, and the fuse doesn't blow...then all you can do is drive it and see if it happens again. It could be a fluke.
If fuse does blow when the fans are commanded on, next step would be to replace the relay, and repeat above test.
If fuse still pops with new relay when fans are commanded on, the next test would be to unplug the wire connection at the fan motors, and repeat test. (note the fans obviously will NOT run with the wiring disconnected, you are only testing to see if the fuse blows w/o the motors connected...do not let the car run long after testing this). If the fuse doesn't blow in that test, it's quite likely one of your fan motors is the culprit.
If they do turn on and run, and the fuse doesn't blow...then all you can do is drive it and see if it happens again. It could be a fluke.
If fuse does blow when the fans are commanded on, next step would be to replace the relay, and repeat above test.
If fuse still pops with new relay when fans are commanded on, the next test would be to unplug the wire connection at the fan motors, and repeat test. (note the fans obviously will NOT run with the wiring disconnected, you are only testing to see if the fuse blows w/o the motors connected...do not let the car run long after testing this). If the fuse doesn't blow in that test, it's quite likely one of your fan motors is the culprit.
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St. Jude Donor '03
