I have a 96 Accord 4cyl with VTEC and my radiator fan comes on when the AC is turned on or when the car is off but refuses to kick on while driving and my temp gauge gets over half to almost 3/4 of the way up. I thought the problem was my radiator cap but that proved wrong. I was thinking about changing the switch and the relay and going as far as changing out the thermostat because my top radiator hose is hot and the lower one isnt hot just warm but I would think that is because the coolant is actually working. Just dont know what to do first and do not want to go replacing things that dont need replacing, so any help would be great thank you so much.

 

Both fans should turn on when the a/c is turned on. If the second fan is not turning on, then you will have to figure out if it is electrical or the fan motor.

If the temperature gauge in the car is rising and neither fan turns on, I would suspect a faulty temperature sensor A on the thermostat housing. If you unplug that connector and short it with a wire, both fans should turn on.

 

Yes both fans work with the AC and the only time my radiator fan works is when I turn off the car because it must sense the hot radiator but it doesnt sense it while driving and the gauge is over half and it should turn on before it even reaches half.

 

The fan relays and fuses are good, since both are working with the a/c on.

I would replace the temperature switch A that is on the thermostat housing. It sounds like that is your problem. You can test if you like. When the engine is getting hot, unplug that sensor and see if the two pins on the sensor are a closed circuit. If not, then you verified the sensor is bad.

FYI: If your car starts overheating, turn on the heater full blast with outside air (no recirculation). That will help cool the engine down and prevent premature head gasket failure and/or engine damage.

 

I have the same problem in my 96 LX 4 cyl. AC fan works when AC is on, but radiator fan won't come on at all. When I'm steadily driving, the temp stays low, but when I'm in stop and go traffic, it gets up to the red, but hasn't overheated yet. When I jumped the sensor connection with a wire, the fan came on. The next day when I jumped it again to show my mechanic friend, the fan don't come on now. Wondering what I may have done to it. Thought it would be an easy fix...just replacing the sensor/switch, but I'm not sure now. Radiator and hoses are brand new. Thanks in advance for any info!

 

Usually best to start your own thread to get more responses.

Fan motor is likely failing due to worn out motor brushes. They get intermittent when brush springs are too loose to force good electrical contact w/ armature. They won't get better and only fix is to replace fan motor. You can confirm by thumping the fan motor w/ a wrench when power is available (AC and ignition On). If fan comes on, then motor is failing.

good luck

 

OK, I'll start my own thread from now on. New to the forum thing. You hit the nail on the head! The fan did come back on while jumping the switch and tapping the fan motor, so I'm thinking it's the fan motor AND switch now. Thanks so much for your advice and sharing. Heading to the parts store now.