What causes the cooling fan to come on?

What causes the cooling fan to come on?

Defective temperature switch, coolant sensor or other sensor. Engine thermostat is stuck OPEN (engine never gets hot enough to turn on the fan) Faulty fan relay. A wiring problem (blown fuse, loose or corroded connector, shorts, opens, etc.)

Does radiator fan come on with AC?

In a nutshell: The radiator fan comes on so the A/C works at its highest efficiency. The A/C condenser (the part which sits in front of the coolant radiator) is a heat exchanger.

How do I know if my AC fan relay is bad?

One of the first symptoms commonly associated with a bad or failing cooling fan relay is an engine that runs hot or overheats. If you notice that your engine is running at higher temperatures than normal, that may be a sign that the relay is not functioning properly.

Why has my fan stopped working?

Whether the blades aren’t spinning or the fan is making tons of noise, most issues with an electric fan are caused by poor lubrication or blockages in the vents. To solve most problems with an electric fan, disassemble the fan, lubricate the central pin and bearings, and clean out the vent and motor case.

What to do if AC fan is not working?

First, go inside and turn off the AC. Then, go check the circuit breaker. The switch you’re looking for should say something like “HVAC,” “furnace,” “AC,” or “compressor.” If the switch is turned off, try turning the switch back on, and go inside and try the AC again.

Should the fan be on when the AC is on?

The fan only runs when the system is on and not continuously. There is better dehumidification in your home during the summer months. When your fan is set to AUTO, moisture from cold cooling coils can drip and be drained outside. If your fan runs continuously, moisture does not have a chance to drip outside.

How do you test a fan control relay?

How to Check a Fan Relay

  1. Look at the markings on top or side of the relay case and locate the two control circuit terminals, which connect to the relay’s coil, and the two power circuit terminals, which let electrical current pass to the fan.
  2. Connect the leads of an ohmmeter to the power terminals on the relay.

What causes a fan to stop working?

Poor ventilation can cause dust and heat to get trapped inside the case of the motor. This can cause your fan to stop functioning—especially if your fan has an overheating feature that causes it to automatically shut off if it gets too hot.

How can you tell if a fan fuse is blown?

Remove the fuse from its holder. In some cases you may need a small screwdriver to unscrew the fuse holder cap. Look at the fuse wire. If there is a visible gap in the wire or a dark or metallic smear inside the glass then the fuse is blown and needs to be replaced.

Why is the fan not working on my Subaru?

When the fan wouldn’t work it wouldn’t blow at all, not on any speed. The lights on the fan unit worked, so it was getting power. Ah, okay. It likely isn’t the resistor pack in that case. It could be a connection to it, tho. Let me dig out a schematic for that car… edit: It also has a fan relay that could be bad.

Is the sub Fan still working with the AC on?

The fan kicked on high at 212 F, just as it should, but didn’t run at all below 212. With the AC on, it ran on high all the time, so the engine temp was actually below 200 with the AC on. The main fan is still working today. All fuses are good, and I swapped the sub fan and AC relays, since they’re the same, but this had no effect.

Why does my Subaru air conditioner shut down?

So, the radiator kept the engine safe, but when the fans were kicking on, they were blowing A LOT of hot air at the evap unit. That would trip the AC temp sensor and shut down the AC. Yes that will happen if the radiator is clogged enough to limit air flow, thus not allowing the proper temp drop needed to take the heat out of the AC system.

What makes up the air conditioning system in a Subaru?

Typical Subaru Air conditioning Problems explained. The Air conditioning (AC) system in your Subaru is made up of the following. A compressor, Condenser, Evaporative (Evap) core, Expansion valve, receiver dryer, hoses and lines, thermo sensor and the controls.