Hello All, Both of my fans never turn on even when AC is on. No Codes
Fuse is good and so is the relay. I swapped with the Horn relay,(same size) and still no go.
I read that if you disconnect the coolant temperature sensor the fan will turn on. It did but not the AC fan, with the AC on.
So... I now know the main fan motor works and very, very likely a bad sensor, so will replace.
Two questions"
1. What's going on with the AC fan?
2. Check Engine light is now on, don't have code yet. I have read that a code May OR May Not be set for a bad sensor. If I reset the code do you think it will through the code again even though it wasn't on before I disconnected it? Just curious.
Thank you very much.

 

When the AC is on power flows to 3 relay coils to power the AC fan.

Code could be anything. If its a bad sensor and it's replaced, the code should eventually go away but may take several drives.

 

Thank you, I've ordered sensor at RockAuto and I'm sure that will fix main coolant fan. I'm not sure about the AC fan... Can you give me more info on testing AC Fan system? Are you talking about 3 relay coils... in the fuse/relay area? what should i test? I don't want to just swap parts. thank you

 

If the engine idles for a long time do the fans turn on/off?

Does the AC magnetic clutch turn on/off?

The relays should be in the "fuse" boxes in engine compartment. One box has 1 relay and the other 2.

AC fan motor positive power from the CDS fuse is turned on/off by No 3 relay. This relay also controls the on/off operation of the AC compressor magnetic clutch. If the clutch works assume the No 3 relay works.

The ECM controls the grounding of the No 3 relay solenoid coil to turn on the No 3 relay. However the other 2 relays are also in this ground circuit also.

The fan relays are not monitored by the trouble code system.

Suggest you pick up some kind of service manual info having a wiring diagram which will make trouble shooting easier.

 

Some follow-up. Installed new coolant sensor and now both main and AC fans start as expected. Next test is to see if main fan starts at idle temperature with AC off.
Curious that Temp gage never went past mid-point when main fan was not starting. Curious...
$10 Sensor at RockAuto
Thanks

 

One More question. On the 04 Camry 2.4... Is there a different sensor for the gauge than the one I replaced for the fans? and location? Please. thank you!

 

The is no "gauge" sensor. There is one sensor that ties into the ECU that sends a temp signal to the gauge.