How To Test a Honda Civic Cooling Fan

How To Test a Honda Civic Cooling Fan


When your Honda Civic cooling fan doesn’t work properly or has failed, it can cause serious overheating issues in your SOHC 1.7 liter engine. These fans are mounted to the back of your radiator and are set to help pull or draw incoming air to lower your engine temperature. If your Honda Civic is overheating or you see the temperature meter going into the red, you should test to make sure your Civic Cooling Fan is working properly.

There are two fans mounted to the back of your Honda Civic radiator. One is the primary cooling fan and the other is actuated when you turn on your air conditioning. Today I will be showing you how to test your Civic Cooling Fan using a digital mulimeter in a 2001 1.7 liter equipped Honda Civic.
How To Test a Honda Civic Cooling Fan 3

Your Honda Civic Cooling Fan with a 1.7 liter VTEC engine is connected by a two pin weatherproof harness. To begin our tutorial you will need to use a digital multimeter to test the engine side of your Civic Cooling Fan harness. Not sure if your Honda Civic is overheating or not? check out our guide here to see if there are any tell tale signs.

Testing your 2001 Honda Civic Cooling Fan for Power

Your radiator fan in your Honda is mounted to the back of your radiator. To begin this test it’s a good idea to perform this tutorial when your engine is cold. Before you start testing your radiator fan, you will need to locate your main cooling fan. Remember you will be testing the main fan and not the air conditioning compressor fan.

How To Test a Honda Civic Cooling Fan 41

To do this you will need to make sure your Civic is sending power to your fan. Start your engine and allow it to warm up. Wait until the temperature gauge on your Civic cluster comes to the midway point. When this occurs turn off your engine and switch the Civic ignition key to the “ON” position.

Unplug your main cooling fan to begin this tutorial, you will be checking the engine harness side of your radiator fan. In order to test your cooling fan properly, you will need to bypass all of the other controls for your cooling fan system.

How To Test a Honda Civic Cooling Fan 4

At this point the coolant temperature sensor in your Civic should be triggered. When this happens your Civic will try to send power to PIN B. Gently probe the engine harness side of your radiator fan and check for power at PIN B. If you check that there’s power at this pin, you will then check for a ground signal at PIN A.

If you have both power and ground at these pins, this may be a sign that your cooling fan is dead. The next part of our guide is to send direct power and ground to your radiator fan in an attempt to see if it works.

Powering your Civic cooling fan

Using at least 12 gauge electrical wire, connect a chassis ground to PIN A of the radiator fan harness. You will now need a power wire from your battery to PIN B. When performing this part of the test make sure to take care and do not touch the wires together, or you run the risk of blowing a fuse.

It’s a good idea to use an inline fuse when performing this part of the test. Once you send power and ground to these wires, your cooling fan should turn on. Because of this fact, you must keep your hands, clothing and tools free of the radiator fans.

If your fan doesn’t click on, you need a replacement Civic fan. Check here for our online store or head to your local auto parts store. Have any questions about this guide? Leave us a comment below and let us know!