Hello, I have tried searching for the possible remedy's for my fan switch not coming on with no clear idea on where to start. I have a hunch that my thermostat may be stuck in the open position, even though the operating temp seems like it should be where it is, I am wondering if it just stuck open and slightly too low to engage the fan. I have jumped the fan switch and it turns on with no problems. Could it be the switch open, or should I replace thermostat? I recently did new coolant lines, water pump. Car does not overheat, temp stays solid right around 3/8s on the gauge. Even when it was 115 degrees out last month it still would not overheat or have the fan come on and temp gauge would not fluctuate at all. Thank you in advance. Car is 1994 honda del sol S 176k miles, no information on when thermostat was last replaced, but it did sit for like 6 years before getting it back up running.

 

So from what I gathered, you suspect the fan isnt coming on but the car doesnt overheat? Honestly if the car doesnt overheat and drives fine, I wouldnt worry about it.

If you are paranoid if the fan is actually working, you could have an assistant watch the fan as the car sit when running in park/neutral and hold the revs to 2000 rpms after about a minute into a cold start to see if the fans actually come on.

For the specific vehicle, if after sitting for awhile with the rpms at 2000 rpms and the gauge looks like its almost half with the fan not cycling on, then maybe a problem has shown itself. Keep us updated.

 

Thank you for the response! Yes I may just be overthinking it, but I have never seen the fan come on until I jumped it. Even in stop go traffic in the middle of a heat wave I never once heard the fan kick on. I read I may be able to test the switch in some boiling water with the ignition on to see if then the fan kicks on just to double check it working correctly.

 

With no airflow, it should eventually come on no matter what. If you've jumped the connector at the switch and it comes on, the next diagnostic step is to replace the switch. Make sure the system is well bled so that you know the switch is staying 'wet'.