How to Know When to Replace a Fan Thermostat

If you have ever been stuck in a city traffic jam and your car gets hot, you already may know when to replace a fan thermostat. First, determine why the vehicle is running hot. Is the fan just not cooling correctly or has it completely stopped working? The chances are that your fan thermostat is not only the least expensive but the most likely culprit. Walking through the symptoms of the problem should show what is needed to fix it.

Difficulty: Challenging

Instructions

Things You'll Need:

• Thermostat made for your model automobile
• Jump wires
• Gloves

1. Examine your vehicle on a pleasant day. Take it for a drive to see if you make the overheating problem reoccur. Back at your garage, open the hood and check to be sure the cooling fan is running.

2. Determine if the fan is not running because of the fan motor or the thermostat. This could take some previous knowledge and skill. You need a jump wire to verify if the motor is working.

3. Unplug the wiring harness from the back of the fan. Attach it to the ground post with the jump wire and ground the fan. Attach the other end of the jump wire to the positive battery post.

4. Run the other end to the positive post of the fan and take a second jump wire and attach one end to negative post of the fan. Attach the other end to any metal part of the body. If the fan is working, it should come on. If it does, then go on to replacing the fan thermostat. If not, stop here and look for a different problem.

Resources

• Automedia outlines auto problems and solutions.
• Forums at Gardenweb site connects problems with repair solutions.

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