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Discovery-94
25th April 2011, 04:16 PM
well well, as the story goes, easter is the time of resurrection - and believe it or not, the disco has been resurrected after months and months spent in the naughty corner (yes, months!)

Anyhow - first of all I hope everyones long weekend is treating them well, of course mine has been oily and greasy so far - but its all been worth it in the end, when you turn that key once again and it starts purring like a little kitten again :D yaaaaay

But (- unfortunately there is always one more thing -) while I spent my last hour or so bleeding the silly cooling system of all its tiny air bubbles the cooling fans in the front turned on before the temp gauge even hit normal operating temperature. (this is the standard LR gauge, have ordered an engine saver/watchdog combo, but since its so many holidays I prob wont receive until end this week..)
Switched the engine off and back on, several times (mainly for refilling purposes) but the fans still came (and stayed) on.

Anyone have an idea what may cause this? I have replaced the two switches on the thermostat housing (not the water temp sensor, the two big buggers) is it possible if I had put them in / connected them the wrong way around (HIGHLY UNLIKELY, but just trying to find an answer) that this would turn the fans on without it being over 100deg?

Just dropping the oil now and letting it cool down to quatripple check the coolant level in the expansion tank.

Any suggestions / comments on the fans would be greatly appreciated.

Cheers,

Simone

omvanders
25th April 2011, 05:08 PM
Simone

Yo don't happen to have your air con switched on do you!!??

Discovery-94
25th April 2011, 05:36 PM
Thanks, but no. air con is off

bigcarle
26th April 2011, 07:40 AM
when i got my 300TDI every-time the ign was switched on, the therm fans worked, i didnt worry about it until i had sorted out some other stuff and eventually found that if i swapped the 2 switches at the thermostat the fans worked only when the air-con was switched on

Discovery-94
26th April 2011, 10:04 AM
yeah, thanks.
did you swap the plugs or the actual switches in the housing?

bigcarle
26th April 2011, 11:15 AM
just the wires/plugs :)

Discovery-94
27th April 2011, 04:59 PM
Thanks.
I actually tried that last night as well.

Been driving, stopped for a little while (no thermo fans while driving or before turning ignition off), back in the car after about an hour, turned ignition back on - and thermo fans switched on immediately.

After a little while I pulled the plugs off both these switches (on the thermostat housing) and swapped them (the yellow one seems to be controlling the fans).

BUT - as I was doing that I noticed in the passenger footwell a "strange noise" - and I traced it back to a little relay hanging off the wire harness around the blower motor. (Posted a thread here in the electronic diagnostics forum to try and identify, if anyone wants to have a look, trying to move to here cos its most likely related)

The relay had water in it :eek: for whichever reason, but since the engine wouldn't start without it, I took it apart and dried it out (with a good spray of carby cleaner ;), put it back in and it works again, but I believe I should have a new relay nevertheless.

Blknight.aus
27th April 2011, 06:57 PM
now pull the relay apart again and treat it to some contact grease or in very short order it will either sieze open or burn its contacts and be an utter pig to diagnose.

Discovery-94
27th April 2011, 07:45 PM
allright. don't think my shed holds contact grease (just yet)... but that shall be changed.

Still having trouble to identify the relay, can anyone hint me in the right direction please (I sound like a complete idiot trying to explain myself on the phone, but working most hours of the day so my chances of bringing it to someone are quite slim :()


Would be fantastic help if someone has a name, number or description of some sort for my newest friend

appreciated!



http://www.aulro.com/afvb/attachments/electronic-diagnostics/35350d1303803148t-need-help-identifying-relay-please-img_7419.jpg (http://www.aulro.com/afvb/attachments/electronic-diagnostics/35350d1303803148-need-help-identifying-relay-please-img_7419.jpg) http://www.aulro.com/afvb/attachments/electronic-diagnostics/35351d1303803158t-need-help-identifying-relay-please-img_7424.jpg (http://www.aulro.com/afvb/attachments/electronic-diagnostics/35351d1303803158-need-help-identifying-relay-please-img_7424.jpg)