cooling fan help.

[GTi Guy]

so im having slight over heating issues with my (hawkeye) impreza. the source of the problem is that the electric fans fail to come on. heating issues happen at idle or when in traffic other than that once moving everything is fine. Did all the checks in teh service and repair manual: so i tested both fans and the work, tested the voltage to the sub fan that works nothing from the connector of the main fan though.. tested the relays and the terminals in the fuse box n fuses everything is good in there.. the sensor and everything work cuz i am getting a temp reading on the dash and with the sensor disconnected the car wont start anyway so i ruled that out along with water pump and thermostat. im running out of ideas so some help would be appreciated even point me to a good mech would help at this point coz im just about given up. thanks

[GTi Guy]

also can any confirm that the sub fan and main fan run off teh same harness? im curious as to why neither is coming on even tho there is a voltage in the sub fan connector

[ramishrrr]

I don't know if your car is different, but cars with electric radiator fans have a sender unit and a thermoswitch.
The sender unit, as the name implies, sends a signal to the temperature gauge on your dash.
The thermoswitch is the unit responsible for switching on the cooling fan(s) sometimes via a relay.
You mentioned "sensor" in the context of a sender unit for the dash gauge. But you failed to mention the thermoswitch. If the checks you made show that the fans are OK, the relay, supply, voltages and wiring are correct, then the thermoswitch or the wiring from it may be at fault.
Regards,
RR.