Hi to all!
I do have a 2002 Focus and has shown overheating problems, I scann the vehicle and had P1474 Low fan control ciruit problems, I check for coolant, thermostat, water pump, ECT sensor, check for shot to ground or power in the wiring harness and looks OK too,... and the fan will not come on at all when running., I check for the relays and work OK.
With the scan I can control the fans (low and high) but when the engine running the fan will not come on.
I think the problem is in the PCM because I can control the fan with the scan as well the fan will turn on when I disconect the ECT sensor located behind the alternator.
Any suggestion or recomendation to get this vehicle running properly.

Looking for your help and thanks for looking in to this request.
Have a nice day.

 

Good Morning to all: I'm still working with this vehicle and I was concern about the coolant temperature in this engine required to have the fan on, do any of you know what is that temperature? I have seen the temperature to get to 108C and the fan is not on.
Thanks in advancec

 

Cyclinder head temp.sensor is the sensor that command the pcm to run the engine cooling fan motor here are some few tips i hope this will help you bro.
Cyclinder head temp.sensor wire color bn/wh going to pcm.wh/vt going to pcm.
Dual pressure switch,wire color bn/rd going to pcm connected to the wire of chts bn/rd.wh/rd goinh to pcm.
Bk/wh coming from pcm is negative going to high speed engine cooling fan motor relay,this negative output coming from pcm is responseble to trigger the high
speed engine cooling fan relay.gn/wh is connected to power hold relay output it si 12v.red wire is connected to 50 amp.fuse.
Gn/bu is connected to secondary cooling fan motor.
Bk/bu is conneted to pcm,this wire is negative signal that trigger the engine cooling fan relay,this relay is different to high speed engine cooling fan relay.
Gn/bu connected to power hold relay splice together with gn/wh wire of high speed engine cooling fan relay.red wire of engine cooling fan relay is
connected to 50amp.fuse.gn/bu output of relay,engine cooling fan relay.is going to fuse 30amp.splice together of cooling fan motor diode.the remaining wire
of cooling fan motor diode is negatve.fuse 30amp gn/bu and gn/wh,gn/wh is going to engine cooling fan resistor,gn/bu wire of engine cooling fan resistor is
going to both wire of engine cooling fan motor gn/ye,and secondary engine fan motor gn/og.the remaining wire of both fan motor are ground.