What is the Condenser Fan Relay all about?

The condenser fan relay connects to the condenser fan and allows it to turn on when the air conditioner in the vehicle is turned on. It enables the cooling fan to pull air through the radiator and the condenser to cool out the vehicle. The relay is part of the cooling fan circuit. Other components include a temperature sensor, control module, and the fan motor.

The relay is the most likely component to fail in the circuit and must be replaced. The relay coil will generally read between 40 and 80 ohms on a test meter. If it reads higher, the relay may be working but is failing and should be replaced right away. If the reading is low, it means the relay has already failed. If you attempt to run the AC when the relay doesn’t work properly, you may cause it to overheat or even result in the engine overheating.

Keep in mind:

• Some vehicles have two fans – one runs the radiator and the other operates the condenser.
• Both fans should come on when the AC is activated.
• When the relay is failing, it may work some of the time but not all of the time – don’t continue to use it without having it checked out first.
• If you gently shake the relay and hear something rattling, it indicates that the armature has broken.

How it's done:

• The condenser fan relay is verified that it needs to be replaced. The relay is located within the main fuse box.
• The defective condenser fan relay is removed from the fuse box and connector checked to be functional.
• The new condenser fan relay is installed into the connection and the fuse box is closed.
• The A/C is turned on and the condenser fan relay is tested for operation.
• The vehicle is tested to ensure proper operation of the condenser fan relay and fans.

Our recommendation:

If the air doesn’t circulate when the air conditioning is turned on, it may indicate a failed condenser fan relay. Turn off the air conditioning system until it can be inspected by one of our expert mechanics. Attempting to use the air conditioning with a bad fan relay can cause the engine to overheat and lead to other problems.

What common symptoms indicate you may need to replace the Condenser Fan Relay?

• Air conditioner fails to work properly
• Air conditioner may work one time and not the next
• Engine is overheating

How important is this service?

It is extremely important to have the condenser fan relay replaced if you plan on using the air conditioner. Serious damage to the engine can result if you attempt to run the AC with a faulty or failed condenser fan relay. If it occurs at the end of hot weather season and you do not plan on operating the AC, you may wait to replace it at your earliest convenience.