4ge thermostat housing sensor

[l1ttle_d3vil]

can someone quickly confirm for me which this sensor is, it comes off the thermostat housing on fwd 4ages. pretty sure its the temp sensor, right?

where is the fan switch located on the 4ages (ae82, ae92 etc)?

[Zak]

Thats the fan switch. The temp, and cold start sensors are on the back of the head.

[l1ttle_d3vil]

thats the temp for the ecu on the back of the head isnt it? what about the temp sensor for the dash? thats what I thought this would've been...

even better if its the fan switch though, thats what I was hoping!!
any idea how it works? when it switches to earth etc? just gota wire up a fan today if I can and will use this switch if possible...

[Zak]

Yup, it switch's to earth. The dash temp is on the water outlet on the head above the waterpump.

To setup the fan up, I would have it going through a relay. Then just hook up a power feed from your ignition to the relay and earth through that switch.

[l1ttle_d3vil]

sweet so just run the negative of the fan to that switch and the postive to the 12v output from the relay?

slightly different to the one on my sr (its a two-pin switch) so just need to make sure im wiring it up correctly!! i assume thread tape on the fan switch will make it useless?

[Zak]

Thats the way.

The tape shouldn't do any thing. I think it's a wax switch similar to a thermostat, so it's all internal. As long as it has water flowing past it should be fine.

[sergei]

if it is 1 wire, then tape could insulate it from housing and you will end up with fan on all the time.

[l1ttle_d3vil]

yeah thats what I was thinking. i've got the fan all wired up, but the switch is on a remote thermostat housing which is bolted to the chassis via a metal bracket.

when I turned the key on the fan will run constantly, as soon as I unbolt the thermostat housing from the bracket (so it was basically 'hanging' and only attached to rubber hoses) the fan stopped.

why is this? should the thermostat housing just not be connected to an earth at all? or should I leave it bolted to the chassis and just remove the thread tape?

[Zak]

S**t, sorry man, I just remembered they switch to open not earth.

I think you will just need to swap the output wire on your relay to 87a or what ever it is.

That way when there is a curcit the fan will be off and when it opens the fan should turn on.

[l1ttle_d3vil]

don't have a relay with the numbered pins etc, which pin would the 87a be?

[Zak]

See here.



87 is the normal out put that you use so the relay is on when it gets the 12v, if you use 87a instead what ever you use will run when the relay is not switched and then turn off when it gets the 12v switching power.

If your relay has 5 pins (Some only have 4) You just need to change over on of your out put pins. It should be the one going to the thermo switch.

If you can't figure it out, pop the cover off your relay and have a look, it'll make sense then.