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Ac fan turns on only on key "on" position


S13Sky

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Can you give us a pic of your jumpers as they are now.  The AC running issue you are experiencing sounds very much like a backfeed through an aux output.  But looking at the ecu schematic and the factory wiring diagram I cant see anyway for that to happen if the jumpers are in the right position.  

As a further test to help rule out some possibilities, could you also completely remove these 2 or 3 bottom jumpers (so you just have 6 bare pins sticking up), then turn ign on to ACC and tell me if the fan still runs.  

kgbbc28.png

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With those J5/6/7 jumpers removed the fan relay wire (pin 9 or 10) wouldnt be connected to anything as far as I can see.  I cant see how the ecu could be causing this fan to run unless someone has moved its wire to some other pin?  

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7 hours ago, S13Sky said:

Pin 11 aux3 for AC clutch. Pin106 inj6 for ac fan.

Are you sure?  All documentation I can find shows the opposite.  With the ignition on, if you set inj6 between "test on" and Off, does the fan turn on and off?

Same with Aux 3, if you set it to test mode and back, do you hear the AC clutch click?

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sorry the cal file wasnt updated.
basically whichever way i set it, aux 3 was always ac fan and inj6 was always ac clutch. should i swap pins on the ecu?

fuel table Cold Start2A (DI EDITTED).pclx

Just swapped it just to see. Same problem but instead of my fan turning on my ac clutch engages. So something Is wrong with pin 11 AUX 3

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This is a back feed issue as I mentioned earlier.  Inj drives dont have a flywheel diode so wont back feed, aux outputs do have a flywheel diode so will back feed if the aux device has power when the ecu is off.    

So the problem is the 12V supply to your AC clutch and Fan relay must be connected to a supply that turns on in the ACC position rather than only in Ign position like it should.  

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Here is the factory wiring diagram.  ECU Pin 11 goes to the AC relay, the AC relay coil gets its supply from ign "on", fuse #5.  

 

YSv6D8G.png

 

And here is the EL power section that is referenced in the first diagram - showing fuse 5 only gets 12V with ign in ON position, there is no connection in Off, ACC or Start positions.  

Z7TXcY9.png

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