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EA81 Thermoswitch Wiring

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I have an MY83 Wagon that has had the electric fan hard wired + - from the battery, to start with the ignitiion. The thermoswitch has a single pole and one wire.

 

I want to re-wire it as original, I have search all over with no luck. Do I connect the Thermoswitch to + or - . Could someone please let me know how it is done ? I have a new switch from Subaru.

 

( and I know most will say leave it hard wired, but I don't want to, so don't tell me ) :)

I have an MY83 Wagon that has had the electric fan hard wired + - from the battery, to start with the ignitiion. The thermoswitch has a single pole and one wire.

 

I want to re-wire it as original, I have search all over with no luck. Do I connect the Thermoswitch to + or - . Could someone please let me know how it is done ? I have a new switch from Subaru.

 

( and I know most will say leave it hard wired, but I don't want to, so don't tell me ) :)

 

the thermo switch in Normally open, and when it get to temperature, it closes (grounds) the circuit. it's what grounds the switching wire for the fan relay.....

 

12V -->Relay Load--> Fan -->Ground

12V -->Relay Switch--> ThermoSwitch/Radiator Ground

I have an MY83 Wagon that has had the electric fan hard wired + - from the battery, to start with the ignitiion. The thermoswitch has a single pole and one wire.

 

I want to re-wire it as original, I have search all over with no luck. Do I connect the Thermoswitch to + or - . Could someone please let me know how it is done ? I have a new switch from Subaru.

 

( and I know most will say leave it hard wired, but I don't want to, so don't tell me ) :)

 

Disconnect the permanent ground from the cooling fan and connect it to the thermoswitch to be stock.

  • Author

so i hook the T/switch to neg :confused: and the other I leave connected to the battery pos :confused:

 

I have no idea when it comes to electronics :-\

  • Author

I must of been posting at the same time you were! Thanks heaps naru .

so i hook the T/switch to neg :confused: and the other I leave connected to the battery pos :confused:

 

I have no idea when it comes to electronics :-\

 

Thermoswitch to FAN negative not battery.

 

Actually,+ side takes power from fuse #4(15 amps) in stock

configuration.

No real problem w/positive side of the fan being hooked to battery positive except that it is now unfused(add an inline one) and the fan will continue running with the key off if the rad is hot enough(normal on many cars).

You could retain your manual switch in order to turn the fan off for deep water crossings and have the best of both worlds.

 

PS-No relay except on turbos.

  • Author

All hooked up and working !

I ended up finding the original wires and the one for the thermoswitch.

So all ended up being easy.

Thanks again for your help guys !

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