02 S60 Ac makes cooling NOT to start.

[sergio]

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If I turn the AC on, the cooling fan will not start. The cooling temps will go beyond boiling point.
I have to stop the car wait a long long time until it cools down then start again.
(brief engine stops won't help the fan to restart have to wait until cool down)

Don't touch the AC the cooling fan works as it should

Where should I look?

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[draser]

Hey Sergio, does the fan work at all?

[regent]

Hi Sergio,

If you have VIDA, you can go to ECM/Activations and do this series of tests with the engine NOT running:

Ignition On, test/activate both cooling fan speeds with and without the AC clutch activated. See if the cooling fan is inhibited with the AC clutch ON and verify if this happens on both sppeds (50% and 100%)
Also, expect to find some active and pending codes that otherwise may not turn the CEL on.

If the clutch ON/OFF does indeed inhibit/re-enable the fan, then the AC compressor would surely buid excessive head pressure and also, you may easiely overheat your engine.

Please post back before you do another test with the engine running.

[oragex]

The A/C is cooling at all (compressor is engaging) ?

It seems an A/C fault inhibits the cooling fan to came on, which in turn overheats the engine.

[sergio]

Hi Regent

The start / stop command of "activations" DOES indeed start and stop the cooling fan on 50% .AND. 100% with AC turned "ON" and "OFF" positions.

I understood by your AC clutch on off that I should turn the AC switch on and off. You didn't mean something like short-circuiting /forcing the AC relay, did you?


Draser

The fan works. Turn the engine on and then right away off, the fan goes on for 5 minutes then stops.


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[regent]

...I understood by your AC clutch on off that I should turn the AC switch on and off...

Negative.
Sorry about the confusion; I meant the following:
In Activations, you can activate/deactivate the AC clutch from the computer (listen to an audible 'click' to verify functionality).
Please do the above test AFTER you have already commanded the fan to run and while you can hear it running in order to check if the fan will drop with the AC clutch ON. Do this for both High and Low fan speeds.

[sergio]

Regent

I tried again and this time I got lost;

A/C relay is always on

when I click on cooling fan ECU this is the screen (on!)

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> cooling fan

monday 84 a.jpg (55.01 KiB) Viewed 1455 times

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and when I click on the fan > start this is the screen I get
Everything goes gray and there is no sound from the fan.

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start stop

monday 84 b.jpg (60.03 KiB) Viewed 1455 times

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this is not what I got earlier this morning

Maybe I should re start the engine run a few minutes turn all off and wait a little bit more?
"Sounds like Jack Nicholson in the China Town"

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[CountryBum-kin]

Bad fan relay?

[regent]

Sergio,
I think you should run the activations test while the engine is not running and ignition key in pos. II
Please try again

BTW, this fan is controlled by the ECU via pulse width modulated signal sent to the fan control module, which is an integral solid state device (not the old school EM relay)

[sergio]

Hi Regent

I will do the test again tomorrow morning (10 PM, now)

I had looked at the electrical drawing and noticed the absence of a relay and I was wondering what the heck... You clarified that. Thanks

BTW I had to drive about 5 miles (return) with a stop for 30 minutes. I didn't touch the Ac.
I got home and checked the fan before stopping the engine. It wasn't running and yet the temp was 220F. reading the android Torque Pro. The needle of the gauge right in the center though.
Stopped the engine, re started a minutes later and voila, the fan began running.
I think the problem is with the fan itself and has nothing to do with the AC.

I have a 300 mile trip planned and don't seem to be able to go there



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