First off id like to thank anyone who reply's ahead of time. I'm having an issue with my cooling fans not coming on. I've tried unplugging the fan switch that is on the lower corner of the radiator they wont come on. They also wont come on when the AC is running. I've used a DMM and checked the relays with voltage (car battery) and all the relays check out. When i turn the ignition (with the fan switch circuit open) the relays click as if to trigger the fans but nothing happens. Does anyone know what the issue is? With the DMM i have confirmed that there is no voltage in the circuit that the relay would close. lost for ideas, ive tried jumping what the relay would connect with a wire directly from the battery with no luck. I ment to mention this earlier but the fans do turn on when directly supplied with 12 v. does anyone know if the relay connects a ground curcuit(-), or a 12v(+). PLEASE HELP and THANKS!

 

The coolant fan system has 3 relays. One fan is the Radiator fan and the other is the Air Conditioner fan.

The Radiator fan turns on when Relay No 1 is closed (ign on which should close the Engine Main Relay to power the other relays).

The fan system has two coolant temp switches. One on the radiator and the other on the upper engine coolant manifold. The manifold switch needs to be closed for the radiator fan to operate.

 

Toyomoho so the manifold switch needs to be closed for the fans to kick into high speed with the radiator switch disconnected? You wouldn't happen to have a wiring diagram would you?

 

The fan wiring circuits are complicated.

The fan system has 3 relays No 1, 2 and 3.

To turn on the radiator fan, relay No 1 switch must be closed. This relay turns power to the radiator fan on/off. This relay switch receives power directly from the 30A RDX fuse. Which gets its power from the engine main relay (when turned on) which gets it from the 100A Alt fuse.

To close the relay No 1 switch, its solenoid needs to be powered. The solenoid is powered when the engine main relay is powered. Which should be whenever the ign key is on.

For the V-6 engine. In order for the relay No 1 solenoid to be operate, the negative circuit of this relay must be grounded to chassis. This can be done as follows:

Via the A/C pressure switch and temp switches on the radiator which are wired in series.

Via the engine control module (for V-6).

Via the ground circuit running through the solenoids of No 2 and No 3. Which in this case would be wired in series. Then through the temp switch on the coolant manifold.

Via the A/C control amplifier/control assy.

See private message for more details.

 

Hello reading your comments I am also having trouble with fans not working. I replaced fan relay #1 this got the fans to come on and off intermittently but only for a few seconds each then off and on. But when the car is running without a/c on the fans will not come on at all. Any suggestions?

 

When the A/C is on, the fans only operate when the A/C compressor is engaged. The fans will cycle on and off with the compressor operation.

Does the car have automatic A/C (auto climate control) or manual controls?