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Discussion Starter #1
Hi all.
I have searched and have found conflicting information. Issue I am having is the aux/electric fan is not coming on with a/c. (I have 2.8 ATQ with main mechanical fan and secondary electric)
I replaced the compressor & drier and had it refilled because the clutch wouldn't engage. Compressor now comes on and I get a/c however the fan does not come on when I turn the a/c on and I didn't notice it come on as I drove home on the freeway, which I figured would have triggered it. A/C blew cold the whole time and no sign of overheating.
I guess first question, the fan SHOULD come on when I turn on a/c, right?

Now I know the fan works as I put 12v to it and it spins up.
Manual says to jump the fan thermo switch. It seemed to have a very small voltage and didn't spin the fans up when jumped.
Next step is to test the coolant fan relay for ATQ engine. I've seen other posts that say there is no relay, but the manual/wiring diag clearly state to test it and reference one. But it doesn't give the number of the relay, assuming under the dash. Does anyone know what that is?
In another post it was suggested that the compressor would not kick on if the a/c pressure switch is bad. Mine engages so I can assume the pressure switch is good?
That I guess leaves me with the coolant fan control module if I can confirm the relay is present/good. I've seen conflicting information where that is located and also that it seems to be a known issue part. Thinking of just replacing regardless, not like it can hurt it.

I'll keep searching but appreciate any insight.

Thanks

J
 

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The fan should run when the a/c is turned on. Without the fan, the car will not overheat and the a/c will work with the car moving in temps close to 100. The a/c will cut out at stops, but the car would still not overheat in temps up to 106 (so far).

The fan controller (or whatever it is called) is under the frame horn on the driver's side for the V6. The relay should be in the ECU box.
 

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Discussion Starter #4
Thanks for the replies. I double check the ECU box. It's confusing because the manual says there should be a relay for my specific engine.
Is there a way to jump the control module for testing to get the fans to run? I see you mention testing for shorts.
 

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Discussion Starter #5
I opened up the ECU box and there was only one relay in there, # 373. Quick check online suggested it was for the fan control module. Along with a large 40a fuse in there. This matches to the schematic in the manual. Tested the relay and it was good so will order a module.
Thanks guys.
 

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The 40A fuse and "373" relay in the ECU box are for the SAIP (secondary injection air pump). These have nothing to do with the electric radiator fan.

In the Bentley manual, schematic 33 (Climatronic) or 43 (manual A/C control) would apply to a 2000 ATQ.

The 40A and 5A fuses for the coolant fan are on the 8-position auxiliary relay panel, under the dash.
 

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Thanks for the correction, I actually have to replace mine as I still have the V6 harness and the 1.8T uses a different setup.
 
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