rad fan switch, 4 plugger ECU L or Vortex

steptoe · Post by **steptoe** » Sat Oct 01, 2011 3:01 pm

Just been trying a short cut to hook up second electric fan on the Vortex.

Never tried this idea before.

I powered up a relay with the intention of tapping into the fan switch in the RHS of the radiator to switch my second fans relay once the switch earths.

I may need diodes or resitors to resolve the temporary hook up.

I tested first. Found to ground the white wire of the fan switch would set off my fans relay, so tapped into that with expectation if fans came on with ignition - I'd just swap and tap off the blue wire.

Problem is, both the blue and white wires of the factory fan switch are earthing out my new fan relay as soon as it is hooked up. My new relay is not wired through ignition - direct to battery so fans would just stay on forever!

The intention was that the earthing function I expected the rad fan to do is not the case, was to do the second fan relay switching and shut down fan #2 some minutes after shutdown.

Disconnected the fan switch wire plug and found both wires see earth.
HTF does the fan work, ECU controlled or goes to a relay somwhere under dash?

I have not tested the plugs output with engine running or ignition on yet .

Now , not understnd that fan switch anymore ???

nncoolg · Post by **nncoolg** » Sat Oct 01, 2011 3:03 pm

They dont use a relay, they just ground through the switch.
I suppose its possible your relay is seeing a ground through the existing fan, try unplugging it, then trying it?

Why not just tap into the existing fans' wiring?

steptoe · Post by **steptoe** » Sat Oct 01, 2011 4:49 pm

'just ground through the switch' bah!

That is what my 87 diagrams show too so gets as confusing as playing with Subie headlights and hooking up driving lights into high beam circuit - the old way :hurrumph:

Great minds thnking collectively here Neville, went out to try just that. I am making up patching leads each time using old two pin square plugs first, just made up smaller round plugs then - and tap of from in between the patching plugs.

The gender changes between IGN OFF and IGN ON at the fan as well. So, went with the flow and got the second fans to switch in at same time. The 85 terminal of relay does not mnd seeing pos in the IGN ON mode while waiting for fan #1 to switch on, and when it does the patched lead goes from pos to neg, triggers my extra relay and fan #2 comes on and off just trailing factory fan,

GREAT STUFF I say to self...then go to switch engine orf , fan #2 turns on.

I can resolve this two ways - supply my relay with IGN on power to 86 or wait for the TM4 to come on the market! Maybe a third is to tap into the other wire at the fan patch in plug !! So the fan patch supplies both 85 and 86 at the relay.

My intention is to do neat wiring installations with this beast. Thinking those small four or six blade fuse fuse boxes. Fit one under dash for IGN ON supply, another for BATTERY for any future accessories.

Caught self out for being lazy this time

Gannon · Post by **Gannon** » Sat Oct 01, 2011 4:53 pm

Not sure if this is XT ro XT6, but it may be of help

steptoe · Post by **steptoe** » Sat Oct 01, 2011 5:18 pm

Thanks for your efforts so far kids

Uploaded with ImageShack.us

Is what I find all over the place. Gotta love the detail of Subies diagrams, so detailed you have to look in about three charts to get complete picture, diagram, wiring codes etc

steptoe · Post by **steptoe** » Sat Oct 01, 2011 5:22 pm

Tweety will be amused to hear that my fans were switching on at 87C and off at 79 - the other day. Today much cooler ambient, 84 and 79 !

EDIT...worked out why the temp drop for switch on - no thermostat fitted at the time...

steptoe · Post by **steptoe** » Sat Oct 01, 2011 6:22 pm

Done and almost dusted. Tapped into both the wires from the loom to factory fan and both had power with ignition on, car running, until the time came for fan to switch on then one turned neg so hooked up to 85, other remained pos so got terminal 86 - nothing tried to burn, and on switch off IGN the #2 fan did not try to come on

A simple test between factory fan and aftermarket-came-with-other-bits-fan , dangled a strip of newspaper in front of radiator while on and the factory one had a marked better airflow than aftermarket.

Took just 40 seconds to bring temp down from 86 to 79 while idling on a miserable cold day in October!

YouTube · Post by **El_Freddo** » Wed Oct 05, 2011 2:14 pm

This is what I've done steptoe, it's for a cab switch, but you should be able to work out how to bypass the cab switch.

I should really intercept the switching at the factory relays but this was easier at the time and I've not really looked into that sort of detail:

Works a treat unless you forget to switch them back on after a river crossing... Just need to be wary about that!

Cheers

Bennie

NachaLuva · Post by **NachaLuva** » Wed Oct 05, 2011 5:39 pm

El_Freddo wrote:Works a treat unless you forget to switch them back on after a river crossing... Just need to be wary about that!

I've been wondering if you can somehow have a big red warning light on the dash wired in that comes on when you manually switch the fans off as a reminder???

Gannon · Post by **Gannon** » Wed Oct 05, 2011 6:36 pm

Just need a 3 position switch that doesnt have an off position, it will have 4 terminals

steptoe · Post by **steptoe** » Wed Oct 05, 2011 6:43 pm

Thanks Bennie, the diagram will be useful for future venturers

I have manualised other Subes quite easily but different. I just don't interfere with the auto function - always armed .

Oh, you've done yours to isolate power with your river driving, not be crossing through any rivers in the Vort.

You could use, nachaluva, another relay for your big red light. An 87, 87a relay. Each position is always opposite to the other like in LPG apps 87 goes to petrol efi pump, 87a goes to LPG supply. Must be a way to configure in with your fans mains off and isolated possie .

NachaLuva · Post by **NachaLuva** » Wed Oct 05, 2011 10:23 pm

steptoe wrote:You could use, nachaluva, another relay for your big red light. An 87, 87a relay. Each position is always opposite to the other like in LPG apps 87 goes to petrol efi pump, 87a goes to LPG supply. Must be a way to configure in with your fans mains off and isolated possie .

Gannon wrote:Just need a 3 position switch that doesnt have an off position, it will have 4 terminals

lol, my big red light hahaha

I'll try that, both good ideas, i'm sure 1 will work...