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Discussion Starter #1
Hi all. I hooked up alfa diag cuz i noticed that my high speed fan dont turn on and temp was rising. When i checked it the fault code came up as follows

P0481

Failed Component Code: Fan #2
Fault Symptom: Short circuit to Vbat
Warning Lamp Status: Warning Lamp not Illuminated
Fault Test State: Test complete for this Error or not applicable.
Fault Code Storage State: Error Present at time of request
Event Count: 40 count
Environmental Condition One: Engine Speed: 160 rpm

I was wondering can anybody point me in the right direction as to what possibly it could be. I tried to test the high speed with alfadiag but nothing happens. My low speed dont work anyway for a long time but now the high speed stopped.
 

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Discussion Starter #4
i have checked the resistor and that is good as this is more or less new i bought cuople of months ago. i think but i am not sure it could be a problem with wiring somewhere.
 

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Have you checked the fan relays?


BTW, not a great idea to have known one fan wasn't working and to have just left it that way... :rolleyes:
 

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Discussion Starter #7
i know i should have fixed the low speed but it seemed fine until the fast speed stopped. It is a single fan. the new one looks exactly like the one on the left on the picture.
 

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anybody what...?
 

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Probably battery +ve
 

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To test the resistor connect the two wires that go to it with a short length of wire (made up properly with two male spade terminals means you can keep it in the glove compartment for emergencies too!).

If the fans work then the resistor has failed. It if doesn't then it's relays, fuses or possibly even the fan motor. Note: The picture on the relay/fuse cover by the battery isn't always right so you might have to try swapping relays, but make sure they are the same amperage, etc.

You can also try pulling the connection off the thermostat sender. the ecu will be unable to sense the temp and start operating the fan intermittently.
 

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Discussion Starter #14
ok so i tried to connect the 2 wires that go in the resistor but nothing happened. i then pulled out the wire from the stat and still nothing happened so i fed direct wire from the fan to battery and it runs so i know the fan is good. i bought new relays and still nothing happened. When i connect a electrical tester (one of those one with a light bulb) and i try with alfadiag then it seems like the is no intermitent earth to the relay.
 

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ok so i tried to connect the 2 wires that go in the resistor but nothing happened.
It won't do anything if the engine is cold or you are not forcing it under alfadiag .. sorry, I should have mentioned that. It just runs the fan in high speed all the time ... when it runs.

i then pulled out the wire from the stat and still nothing happened
Ignition on? Then I'd say this was a power problem. You have tried the fuse under the bonnet? Big black unit near the brake reservior. Big fuses too!

so i fed direct wire from the fan to battery and it runs so i know the fan is good. i bought new relays and still nothing happened.
The diagram on top of the relay cover near the battery has been known to show the wrong position for the fan relay and can also be worn off. Have you tried the others?

When i connect a electrical tester (one of those one with a light bulb) and i try with alfadiag then it seems like the is no intermitent earth to the relay.
Connecting to what? relay, fan motor? If you aren't getting power at the relay or motor, then you probably have a blown fuse or break in the wiring.
 

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Discussion Starter #17
i tried connecting the fan direct to battery and it worked. the fuses are all ok and the position of relays on diagram are right. when i did dissconect the wire from stat ignition was on. davidc looks confused with me writing intrmitent earth, what i really meant was switching earth what alfadiag does
 

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davidc looks confused with me writing intrmitent earth, what i really meant was switching earth what alfadiag does
This is what you wrote:
"...it seems like the is no intermitent earth to the relay."

The sentence doesn't make any sense, that is why I was confused!
 

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Discussion Starter #19
ive been looking at the problem with my fan and it seems to be a wiring broken somewhere. when i lift the fuse box up next to battery the it seems to kick in with alfadiag. now that i have fiddled with it it dont seem to work at all so i am assuming that i have totally broken the wire. does any body know which wire it could be under the fuse box which the ecu switches earth. i know that the are two big connectors with loads of wire (black box and a brown colour box) then there is two wire that run from the fuse box direct to fan, the there is another block with just a red and black wire and another block next to that withe two wires (red & black & red on its own.)
 

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Discussion Starter #20
Hi all, justaupdate. I checke all the fuses and relays and they are all good. I put a wire from pin 86 on fast speed relay and nothing happened, i then dissconected the wire from stat and still nothing, any body know what else it could be as iv tried tonarrow it as much a possible.
 
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