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Old 6th June 2019, 16:45   #51
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Phil, check THIS out, hope it helps.
Just what the doctor ordered.
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Old 6th June 2019, 18:35   #52
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Thanks for that Wes, that's a great resource.

Looks like its pointing towards an ECT problem.

Do you know where the ECT is located?

Also, reading that, it says that if the fan is cycling on and off on a kv6 (as mine seems to be), it may indicate a faulty low speed, perhaps I need a new fan.

If that's the case, would it be better to replace the 3 speed fan or fit the newer 2 speed fan?

Phil
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Old 6th June 2019, 20:11   #53
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Thanks for that Wes, that's a great resource.

Looks like its pointing towards an ECT problem.

Do you know where the ECT is located?

Also, reading that, it says that if the fan is cycling on and off on a kv6 (as mine seems to be), it may indicate a faulty low speed, perhaps I need a new fan.

If that's the case, would it be better to replace the 3 speed fan or fit the newer 2 speed fan?

Phil
The fan cycling on and off sounds like an aircon fault, low in gas. Did you say you had it regassed recently?

The coolant temp sensor is in the middle of the V on a V6, just in front of the thermostat housing. You can get to it by removing the throttle-body and going in from the side/rear, its not as hard as it looks. Did you say you had a new thermostat fitted about 3 years ago, was the sensor changed then?

Front left (two wires). Also, have you checked in this area for puddles of coolant?


You can test all three fan speeds using THIS method.

If you find your fan isn't working on all speeds, you can replace the bushes within the fan motor yourself with just a few clever skills needed.

Your fan seems to be working ok by the sounds of things, but if you do end up replacing the fan, I myself fitted the same 3 speed setup.
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Old 6th June 2019, 20:21   #54
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Two speed fans cycle on and off when A/C is on when the resistor has failed. I have also known a three speed fan cycle on and off when A/C is on when the slow speed has failed due to brush wear.

At no point through this thread has the OP mentioned the fan cycles on and off when A/C is on.

This needs to be clarified.
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Old 6th June 2019, 20:30   #55
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I was meant to say, you can also check the temp sensor is working using the OBD 19 & 7 method. Check the outside temp on the OBD is the same as your coolant temp by using the 19 & 7 procedure, turn key but don't start the car.
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Old 6th June 2019, 20:36   #56
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Hi Phil,

You say that the temperature increased from 95 to 110 at idle. Mine would struggle to reach 100 under those circumstances so my fan would never start running. I wonder whether Mr. Previous Owner put K-seal in the cooling system making it inefficient.
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it says that if the fan is cycling on and off on a kv6 (as mine seems to be), it may indicate a faulty low speed, perhaps I need a new fan.
You haven't mentioned the cycling fan before. That would explain a lot if you have a 2 speed fan and not a 3 speed. Perhaps your car is one of the few to have a concealed resistor. Do you fancy taking the bumper off?
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Do you know where the ECT is located?
In the 'V'.

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Old 6th June 2019, 20:42   #57
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The fan cycling on and off sounds like an aircon fault, low in gas.

I don't think that's right Wes. Low refrigerant would result in the trinary switch disabling the compressor.
Quote:
You can test all three fan speeds using THIS method.
The high speed cannot practically be tested on a 3 speed fan, only the low and medium speeds.

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Old 6th June 2019, 21:05   #58
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Two speed fans cycle on and off when A/C is on when the resistor has failed.
Quote:
Originally Posted by SD1too View Post

That would explain a lot if you have a 2 speed fan and not a 3 speed. Perhaps your car is one of the few to have a concealed resistor. Do you fancy taking the bumper off?

Simon
Eureka! could this be the problem?
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Old 7th June 2019, 02:57   #59
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Hi All,

Many thanks for all the above advice, it's very informative.

The fan cycles on and off on demist and air con calls.

I didn't realise this was an issue so didn't mention it.

I assumed a 3 speed fan because there is no visible resistor, however, I have recently seen a picture comparing 2 and 3 speed fans.
My fan does have the moulding with 2 screw holes at around 2 o'clock where a resistor could fit, the picture I've seen of a 3 speed fan doesn't have these holes.

So it may be a 2 speed with the resistor either missing or mounted elsewhere.

There does not appear to be any sign of coolant loss from the V.

I think that covers all the above questions.

Soooooo.....

I guess that means a couple of things.

I may have a dodgy sensor in the V (although if that was the case, does that mean I would not get an accurate temperature from the ECM?).

I may have a dodgy, or missing resistor, or a dodgy fan?

Should I change the sensor?

And/or

Replace the resistor (assuming I find a 2 speed fan when the bumpers off?)

And/or

Replace the whole fan assembly.

Could I have everyone's views on which of the above, and in which order?
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Old 7th June 2019, 07:27   #60
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I have refrained from posting on this thread too much as too many cooks etc, but as you have asked for opinions.

The bracket for the resistor is a red herring, pay no attention to it. both two and three speed fans are fitted to the cowling with this bracket.

My opinion.
Your next step is to repair/replace the fan, so its a bumper off job.

Then you need to identify the type of fan.

Two speed will almost certainly be a resistor fail BUT it could be the relay in the control box ( also a bumper off job.)
Three speed will almost certainly be brushes worn away but equally small chance it could be a relay fail.

Once you have identified the fan type and proved the relays to be good you have a number of options the choice is yours:

Three speed:
1, Attempt replacement of brushes:
An amount of mechanical aptitude is needed along with a high capacity soldering iron. This can usually be achieved if not all the speeds on the fan have failed and is relatively cheap.
2. Replace the fan with two speed and new resistor ( Plug and play)
3. Replace the fan with after market ( Small amount of rewiring)

Two speed:
1. Usually changing the resistor solves the fan problem, soldering of the new resistor is advisable as opposed to dry fixings
2. Replace the fan with replacement 2 speed and new resistor ( Plug and play)
3. Replace the fan with aftermarket. ( Small amount of rewiring}


Once you have rectified the faulty fan you can then move on but as SD1too says there could be further issues but then again there may not.
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