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radiator fan engage what temp?

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I recently changed my radiator fan trigger from manual to ecu controlled.  Around what temp should the ecu be triggering it to come on?  They haven't come on yet.  The factory gauge(with resistor) reads okay and the manual gauge (upper radiator hose) stays around 180*F in 80*F weather.  I have gotten it up to 210*-215* at long stop lights, but still no fan.?

 

I have it wired like this through bosch relay:

Batt+  power = 30

 

12v out to fan = 87

 

Ig. switched power + = 85

 

ECU fan trigger (ground) = 86

Edited by Carl B.

  • Author

also no codes for temp sensor.  No a/c installed so I didn't do a secondary fan.  

 

Now that the weather is warming up Im getting a paranoid of blowing a head gasket etc.  I do have an ej25  :P

Hmm....ECU should trigger it on around 205

 

relay config sounds correct.

 

maybe switch the 85 and 86.....the relay coil might not like revered curr3nt?

  • Author

switched 85 and 86 no change, so

 

I started shooting wires and found out the ECU signal wire has no voltage above or below 205.  Also no continuity to ground above or below 205.

 

Not sure where to look next, since I'm getting no code for the temp sensor.

 

additional info:

 

2001 25rs ECU

134a pin 3 ECU signal, red/light blue wire

My info shows the fan control wires at a different connector.

 

I show B134, pins 13 and 14 as the fan wires......14 is main, 13 is sub.

 

That is from a 2003 Legacy FSM so might not be correct for you but it's for a 2.5 of that gen.

  • Author

B134 13 and 14 go to #2 and #3 fuel injectors respectively.

 

I verified the wire I'm using in the FSM for the donor vehicle.  Its listed as "radiator fan relay 1 control"  

 

"fan relay 2 control" has a note stating "with a/c vehicles only"  

 

I think I need to shoot the temp sensor or scan codes when the engine is above 205*  

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