Gold Resistor Fitting

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Originally Posted by Rsnail

One question that I have is how do I find out if either the resistor is the culprit or the fan motor or something else if my fan doesn't work at all?

A failed Demist Test defines a failed low speed fan. Assuming the power supply, the relay and earth wiring is sound, no further tests are needed. The high speed should be OK. If you need a high speed test, disconnect the coolant temperature sensor and start the engine. The high speed emergency cooling should trip on.

TC

[Rsnail]

And how do I actually proceed to making these tests? I actually don't know what a demist test stands for, but if I'm not wrong it is the test which you turn the AC on and wait for the fan to kick in, tried that, didn't spin at all.

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Originally Posted by Rsnail

And how do I actually proceed to making these tests? I actually don't know what a demist test stands for, but if I'm not wrong it is the test which you turn the AC on and wait for the fan to kick in, tried that, didn't spin at all.

With the cool engine ticking over, press the Demist button. That invokes the aircon system, which should trip on the radiator fan at low speed. This should happen within a second or so. If not, the low speed has failed.

With low speed failure, after about 30 seconds the fan will trip on at high speed and cycle off-on-off-on every 20-30 seconds. That's the emergency aircon cooling system in operation. A similar result can be seen by running the high speed test by disconnecting the coolant temperature sensor as described earlier.

TC

[Jules]

Fan speed tests on link below
Far easier to test the middle or high speed via the trinary(depending if 2 or 3 speed)

Very very awkward to disconnect the temp sensor on a V6 Arctic !!

http://www.the75andztclub.co.uk/foru...ad.php?t=35567

[Arctic]

[QUOTE=Jules;2452697]Fan speed tests on link below
Far easier to test the middle or high speed via the trinary(depending if 2 or 3 speed)

[QUOTE]

Very very awkward to disconnect the temp sensor on a V6 Arctic !!

https://www.the75andztclub.co.uk/for...87&postcount=1[/QUOTE]


HI Jules.
I have to agree I would not like to disconnect the V6 temperature sensor on a V6 either, i would like to make it clear that i have not advocated this in this thread, or would not advocate it.

As you say it is very awkward, mainly because the ECT sensor resides next to the thermostat at the top of the engine, therefore not accessible unless you remove the air cleaner and the inlet manifold.

I prefer to use our T4 to check all the speeds on any fan, we are lucky that we can do that because we have a full T4, but for the members whom do not then i would say your link above is the best way to test. Arctic.

PS the diesel temp sensor is not much easier at least the manifold is easy to remove.

[T-Cut]

Originally Posted by Jules

Very very awkward to disconnect the temp sensor on a V6 Arctic!!

Originally Posted by Arctic

I would like to make it clear that I have not advocated this in this thread, or would advocate it.

It was me. I'm sorry if I mislead anyone. I didn't bother checking into which engine Rsnail has in his 'Rover 75 saloon'. So I'm standing in the corner wearing a silly hat - and I'll not be allowed any tea.

TC

[Jules]

The only 2 engine variants to easily disconnect the temp sensor are 1.8 or V8 but not recommended on V8 as it throws the MIL lamp up for a good few journeys until it resets.

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Originally Posted by Jules

- - - not recommended on V8 as it throws the MIL lamp up for a good few journeys until it resets.

Is that because of a difference in the speed the v8 communicates? I think I read somewhere that the baud rate is different (slower??) from that used by the KV6/K16/M47R (9600??)

TC

[Arctic]

Bumping this up for Gavin and any others to find if they are changing a silver resistor for a gold one.