This is a tough one. I have feeling your fans are probably both working as they were designed. If this is the case, you might be better off cutting the appropriate wire to the IRCM (You can do a search on IRCM to find this procedure).
Yes, the fan works when the A/C is turned on, but ONLY if the A/C if full of freon. If you’re A/C is low on freon, the A/C will not come on, hence, the LS fan will not come on.
The IRCM is in front of the air box, which contains both of the fan relays.
I would have guessed the fusible link to the IRCM was shot, but you said the fan comes on when you unplug the ECT, so that means the relays are getting power.
You should at least check the IRCM and fan combination by running a quick check with jumpers and the Key On Engine Off (KOEO) test. Here is the procedure from another thread:
Here's how I determined IRCM and fan both worked normally:
I used non insulated spade connectors and 3 pieces of insulated 14 ga wire to make jumper cables running between the female fan connector and the mating male connector on the fan cable harness. I suggest making the wire just long enough to reach between the fan connector and the car battery (I'll explain later).
Leaving the black ground jumper in place, disconnect one of the other power jumpers, then run the KOEO test and listen for the fan to come on. Reconnect the power jumper then disconnect the OTHER power jumper and repeat the KOEO test and listen for the fan to come on again.
If the fan came on both times when running the KOEO test, your IRCM and both fan coils are working fine and you problem is elsewhere. The KOEO test actually functions both fan coils, but it happens kinda fast making it hard to tell which fan speed(s) turns on. Doing it this way, you are sure each functions.
If the fan fails to run on one of the KOEO tests, disconnect the 3 wires from the male side of the harness leaving all three connected to the fan moter. Touch the ground to the negative battery terminal and each of the power wires to the positive battery terminal ONE AT A TIME. By the way, this is gonna spark because if the current draw, so be warned! If one of the fan speeds still does not work, one of your fan coils are dead and you need a new fan moter. If both fan speeds work when connected to battery ... your IRCM could be the problem (or the problem can lie upstream of the IRCM).
Fordrunner38 said:
Can you offer some assistance regarding my coolant fan notcoming on as it should. Neither the LS or HS works. my AC is also not working. I understand the fan works through the AC. Is this Correct. In any event, I replaced the ECA i guess this is the box in front of the air flow black box, same results after the swap. my connector is good and the fan works straight off the battery. i have noticed when i unplug the sensor(is this the ECT?) behind the DIS module the fan comes on.
How do i rectify this problem as i need to do highway driving soon and don't want to rely on using the LS fan constartly on the 2 hour trip. also, where are the LS and HS fan relays located? Maybe these relays are bad and are causing this problem. Please advise ASAP. Thank You