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Radiator fan at low speed & fan control
- Thread starterNabeel
- Start date
Muskrat
Well-known member
This is just a guess, you'll need to learn to read the electrical diagrams and confirm for yourself.
The fan switch in the radiator controls low speed operation. Instead of running the switch, wire an automotive relay up to a switched power source, and run the fans directly from that, instead of the stock fan switch.
The fan switch in the radiator controls low speed operation. Instead of running the switch, wire an automotive relay up to a switched power source, and run the fans directly from that, instead of the stock fan switch.
Good answer for the low speed constant operation idea. Not so sure without the temp switch signal that it will ever judge the need to go to high speed. Or does the high speed only run when the AC condenser fan is on? I can't remember.
Muskrat
Well-known member
I could be wrong, but I was under the impression high speed control was based off one of the t-stat housing sensors. I think the switch in the radiator is just that a switch. If it needs to be "ON" for high speed operation, your right.
However, here's another, better, idea: Unplug the fan switch and short the wires. That should do exactly what you want, be really simple, and as far as the circuit is concerned the switch would always be closed.
Again, I highly suggest doing the appropriate research and checking out how everything is wired with the circuit diagrams in the FSM.
However, here's another, better, idea: Unplug the fan switch and short the wires. That should do exactly what you want, be really simple, and as far as the circuit is concerned the switch would always be closed.
Again, I highly suggest doing the appropriate research and checking out how everything is wired with the circuit diagrams in the FSM.
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Actually I did alot of search. there is no clear answer on how GVR4 cooling system works. some electric maps available I thing from the manual. But I could not understand the theory. Recently booth fans will run at high speed only when gets hot. I think it is by the ECU through the temp. sensor. the switch under the fan is new. I am not sure how to bypass the Fan resistor & it should be wired as stock now. both fans will also work at high when AC is ON. I tryed to bypass the radiator switch ...no change..I tested the relays & fuses. They looks fine. Note: the thermostat is new & radiator is also new with fresh cooling water.
Alainb7
Well-known member
The system is very simple.
You have 2 relay in the fuse box. They are id as Rad Fan. The one nearest the shock tower is the Lo speed one. The middle one is the hi speed one.
The Lo speed relay is activated by the sensor in the bottom of the radiator. It is a 2 wire connector) It start at 185f and stop at 172f.
To go lo speed, the negative wire of the fan is bypass via the fan resistor (bolt on fan housing).
The high speed relay is ativated by the sensor behind the thermostat housing. It is a 1 pin sensor with a Blue wire with a black line on it. It start at 215f and stop at 206f.
If you want to have the hi speed relay activated at on switch position, just unconnect the connector from the 1 pin sensor with a Blue wire with a black line on it behind the thermostat housing and put it to ground.
If you want to have the lo speed relay activated at on switch position, just unconnect the connector from the 2 pin sensor on the radiator, just made a jumper between both pin.
In both case, fan will start at on position because the positive activation of the relay is only powered at on position.
Me what I do is to use 2 fan in High speed. I do not have no more AC.
I want to use AC fan as first to start (To force air to pass true the rad to prevent turbo to heat-up the rad) so i leave the hi speed system to start the Pull fan when temperature hit 215f in the engine.
And i modify the lo speed relay system to start the pull fan (AC oem one)but at hi speed.
I remove the 3 srew that hold the fuse box to acces the wire under the fusebox.
I cut the 2 wire of the lo speed relay (Blue wire with white line and cut also the blue wire) Carefull, both lo & hi speed relay has the blue wire with white line.
Insulate the 2 wire you just cut that go in the wire hardness to prevent short.
Then use the 30a fuse of the AC to feed the AC fan. You cut the Black wire with white line and bring it to the blue wire of lo speed relay, then pass a new wire from the blue wire with white line of the lo speed relay and bring it to the fan.
You cut both wire of the fan, plug the new wire and the other wire of the fan, just put it to ground.
Again, insulate the 2 old wire of the fan to prevent short.
You have 2 relay in the fuse box. They are id as Rad Fan. The one nearest the shock tower is the Lo speed one. The middle one is the hi speed one.
The Lo speed relay is activated by the sensor in the bottom of the radiator. It is a 2 wire connector) It start at 185f and stop at 172f.
To go lo speed, the negative wire of the fan is bypass via the fan resistor (bolt on fan housing).
The high speed relay is ativated by the sensor behind the thermostat housing. It is a 1 pin sensor with a Blue wire with a black line on it. It start at 215f and stop at 206f.
If you want to have the hi speed relay activated at on switch position, just unconnect the connector from the 1 pin sensor with a Blue wire with a black line on it behind the thermostat housing and put it to ground.
If you want to have the lo speed relay activated at on switch position, just unconnect the connector from the 2 pin sensor on the radiator, just made a jumper between both pin.
In both case, fan will start at on position because the positive activation of the relay is only powered at on position.
Me what I do is to use 2 fan in High speed. I do not have no more AC.
I want to use AC fan as first to start (To force air to pass true the rad to prevent turbo to heat-up the rad) so i leave the hi speed system to start the Pull fan when temperature hit 215f in the engine.
And i modify the lo speed relay system to start the pull fan (AC oem one)but at hi speed.
I remove the 3 srew that hold the fuse box to acces the wire under the fusebox.
I cut the 2 wire of the lo speed relay (Blue wire with white line and cut also the blue wire) Carefull, both lo & hi speed relay has the blue wire with white line.
Insulate the 2 wire you just cut that go in the wire hardness to prevent short.
Then use the 30a fuse of the AC to feed the AC fan. You cut the Black wire with white line and bring it to the blue wire of lo speed relay, then pass a new wire from the blue wire with white line of the lo speed relay and bring it to the fan.
You cut both wire of the fan, plug the new wire and the other wire of the fan, just put it to ground.
Again, insulate the 2 old wire of the fan to prevent short.
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Posted this in another thread. Looks like it would help here as well.
KiNgMaRtY
Well-known member
It seems that my fan does not kick on at high. Which sensor would it be? The sensor on the thermostat? I always thought that was for the gauge?
