now, if only Texx would share a schematic of his explanation above..
so Stu-, it so happens that this didn't quite work as i'd have imagined. i unplugged the thermo switch at the stat housing and nothing. ignition was on but engine off -- i just wanted to test the theory. will try again with the engine running but i doubt this will change anything..
i then decided to do some further research. the wire leading to the thermo switch carries 12+ vdc juice that is ignition controlled (offline when the key is at 'off').. so this makes my work even easier. will just add a tri-pole switch in-between as shown in this schematic and extend the wires into the cabin. depending on which switch i'll get -- whether the on/auto parking pole switch on the right side of the steering, or the boost hi/lo/hazard/defrost switch that reside on the centre console -- i'll then decide how long to pull the wires..
this will work a treat given that it's been so hot of late.. i'm sure the engine will be happier..
i'm under the assumption that the thermo-switch-to-rad-fan-relay wiring is only within the engine bay (thermo switch to fuse box) and does not get into the cabin at any point. can anyone confirm this..?
thanks Texx for your very detailed explanation on this, however, (i think) i have a slightly different experience with this. earlier on today, i went tinkering around the bay and when i ground the thermo-switch plug, the rad fan comes to life (with IGN on). this leads me to think that the thermo-switch is a NO (normally open) switch when cold and as it heats up, resistance drops to near zero which then completes the relay circuit and triggers the rad fan.
now i know everything i'm saying is the direct opposite of what you have just explained.. but this is something i did practically. is it possible that your got your explanation(s) right but only swapped your 'open' & 'closed' definitions..?
did you guys figure out where these wires go? i have a glanza V and am trouble shooting my fan not running, the fan will run when i turn the AC on but i dont believe it is coming on when engine reaches operating temp, does the fan always kick in on your drive or only in the sweltering heat? My guess is the relay or the temp sensor is badEvery day is a school day, you learn something if your eyes are open.
Thats the problem with helping out sometimes, you end up being wrong!
Maybe you can trace the relay wires dark_knight and see where they go, it would be good to know.
Going back to the original thread topic, if you wire a switch in so that when the contacts are open it will break the rad fan switch wires and closed it will continue the circuit, you will have auto/manual control.
Thanks, yeah my glanzas fan will turn on with the AC on, so the fan itself works, ive ordered a new cooling fan sensor, is there a way i can test this sensor in the meantime?It'll take a long time at idling from cold before you hear the fan come into play in my experience. Probably around 15 mins depending on ambient temp. A long hot run would help work out if there's an issue, note it only kicks on for short bursts too.
Will try to hoke out the testing procedure later from the manuals.
If there's a break in the fan switch wiring the fan will just run constant so you can rule that out at least.
EDIT - Bollocks, just realised you're talking about the glanza version, my bad! In that case I might not have the books and your wiring doesn't have the failsafe. I should have read the thread. Let me have a look later at what I can find.