Fan switch, or ECU controlled?
#1
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Fan switch, or ECU controlled?
Just a quickie, are the rad fans ECU controlled? I cant for the life of me find the fan temp. switch if they are not
I want to wire up a by-pass switch, I assume there is ground or +12v signal from the ECU I can switch to activate the fan relay?
Cheers for any help
I want to wire up a by-pass switch, I assume there is ground or +12v signal from the ECU I can switch to activate the fan relay?
Cheers for any help
#5
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you can just run 12volts to the fan motor..
3 wires from memory.. red (12v) white (variable speed) black (ground).
I THINK I just ran 12volts to the red wire and the fan runs at full speed..
check with a volt meter to be sure though.
Simon
3 wires from memory.. red (12v) white (variable speed) black (ground).
I THINK I just ran 12volts to the red wire and the fan runs at full speed..
check with a volt meter to be sure though.
Simon
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on the phase 1 for example the ecu drops the voltage from 12volt to 0 to switch the relay.. therefore if you find that wire to the relay and ground it..
the ecu will still be sending 12volts down it..
My electronics knowledge is not huge but I think you need to run a new relay or wire straight to the fan like I did.
Simon
the ecu will still be sending 12volts down it..
My electronics knowledge is not huge but I think you need to run a new relay or wire straight to the fan like I did.
Simon
#12
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Thread Starter
Wont have a chance to play for a while as we're off to a wedding..
Got a horrible feeling the thermostat isnt opening as soon as it should either, I let the car warm up to half temp on the gauge (took a while) then checked the bottom hose, it was stone cold!
Got a horrible feeling the thermostat isnt opening as soon as it should either, I let the car warm up to half temp on the gauge (took a while) then checked the bottom hose, it was stone cold!
#13
Can't i simply rig a switch to (on closing) send 12 v to the fan relay (same pin on the switch that the ECU pin is connected to) and that will trigger the relay to close and send 12 v to the fans?
If the manual switch is 'on' and the ECU sees a water temp high enough to signal 'fans-on' then the relay is simply closed when it tells it to, so 'safe'.
Is it realy that simple?
Help!
Graham
If the manual switch is 'on' and the ECU sees a water temp high enough to signal 'fans-on' then the relay is simply closed when it tells it to, so 'safe'.
Is it realy that simple?
Help!
Graham
#15
Just thinking about this. Unless the rad fans are 'sealed' to the rad/FMIC (which mine are not) the fans switch on will have little effect on force cooling the FMIC core?
Is this a waste of time??
Graham
Is this a waste of time??
Graham
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