Hiya,

is there any way to test the operation of the air con fan that sits infront of the condenser either manually or via IID?

The multiplug is 3 pin, live, ground and I am guessing the 3rd is a switching feed from the ECU, so just putting 12V across the live/ground doesn't work.

Trying to figure out if the fan has gone as it isn't cutting in when it should or whether it is a sensor.

Cheers

Paul. 2011 TDV8 AB
2006 TD6 AB (Gone to Wales)

This good 'ol boy does a good job of explaining it all



Unfortunately, the fan control is separate from the power to the fan.

Don't see why the fan won't run if you give power and earth, but as you say the controller is probably on the fan!

Also, given you have a TD6, is the engine getting hot enough to require the fans to come on? Your viscous fan will be taking care of most of the cooling needs. .
Experience is the only genuine knowledge, but as time passes, I have forgotten more than I can remember
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Previous: L322 Range Rover TDV8 3.6 2008; L322 Range Rover TD6 3.0 2002; P38A Range Rover V8 1999

I have been working on a TD6 2006 as it's immobilised but I got the ignition to turn on and we have been running various diagnostics and I noticed smoke pouring out from the front grille from the fan motor.
I disconnected the 3 pin multiplug straight away. I tried it again a week later and same thing. I tried connecting a battery to the two main cables going to the fan and although the fan would twitch it wouldn't spin so it's staying disconnected for now until it's mobilised and I can test it properly.

Thanks for the link Joe, but as you say slightly different setup to the RR. The 3rd wire on the RR I am pretty sure is some sort of switching feed, so the motor probably gets 12v permanently and is then switched by a low voltage feed from the ECM. That is why just hooking it up to the battery doesn't do anything, or as HC observes just gives you a momentary twitch.

The condenser fan isn't really about engine temps, it is independent of the viscous as it is about keeping the pressure/temp of the a/c refrigerant down. If the refrigerant heats up/gets to high pressure it cooks the gas which then becomes useless, so the condenser fan kicks in to keep the pressure down.

The viscous does help as its cooling effect gives some aid to the condenser but the two systems are independent from what I understand and whilst you could run without a viscous, you can't run without a condenser fan (or at least in summer) as the temps will cook the refrigerant.

So still looking for a way to test, might put a meter across the 3 wires to see if I can see what voltage the switching circuit is and check it is getting a voltage i.e. not the sensor that is fubar.

Would be nice if IID could help.....

Cheers,

Paul. 2011 TDV8 AB
2006 TD6 AB (Gone to Wales)

You are right about the switch feed, but not so sure you are right about where it gets its info from (although what you say makes sense!).

Here is the Air Conditioning wiring diagram (admittedly for '02-05 models), I have marked items of interest!