watson10

On my 96 Accord 2.2 4cyl. I installed a new radiator after the top tank cracked. Up until this point the car never overheated. After installing the radiator, I notice the temp. rising in stop and go traffic. I found out that the radiator fans were not coming on. Then after I turned the car off one of the fans came on. I tested it again and then both fans came on while the car was idling and stayed cool. I tried it again and the fans would not come on while running and overheated, but would while come whil off.

Any ideas?

Tom

Nightshade

Wow thats a really random problem :thinking:

Are you sure all the connections to the fan assembly are solid?

96JdmAccord

Ive delt with the same problem that you are dealing with for the last 6 months. It ended up I had not radiator fluid in my radiator and I filled it to the top and I have had no problems in the last 2 weeks. I re-filled the container all the time but never thought about the radiator.

You should also (forgot the name) were basically you drain the water and fluid's out of the radiator/engine about 4 times and that could lead to the problem.


**EDIT** I was gearing that post more towards other reasons it would be overheating. Nothing to do with the fans.

watson10

Yeah they seem to be. It was the first thing I checked.

watson10

Yeah, thanks for the edit. After the radiator installation, I filled with 50/50 antifreeze and bled the bleeder.

Thanks anyway.

Nightshade

I would say temp sensor possibly or thermostat going bad I think they are related to each other closely but I really couldn't honestly say one or the other or how to test them accuratley.

I do know that to check if the thermostat is going bad you can just remove it and run it open but the thermostat really shouldn't have anything to do with the fans kicking on so my guess is going to be temperature sensor not sending an accurate read to the fan assembly.

I am kind of grasping at straws here and hoping something leads to the cheapest option as well as a fair diagnosis.

watson10

Thanks for your guesses <smile>. Is the sensor for the cooling fan on the thermostat housing? There is also a sensor on the water outlet (the top rad. hose connection), do you know what that sensor is for?

Thanks,

Tom

JimBlake

There's 3 temperature 'sensors', Honda moved them around some over the years. My '95 Integra & '98 Accord both have the same story for those, so maybe your '96 is the same. These 3 separate systems don't 'share' information with each other.

The fan switch is in thermostat housing, it has a plug with 2 wires. Just an on/off switch, it's not really a 'sensor'. Unplug it, jumper the wires together, turn on the key; that should make the fans run.

The engine coolant temperature (ECT) sensor is at the upper hose nozzle, it's also got a plug with 2 wires. That's for the fuel injection ECU to measure temperature.

The sender for the temperature gauge on the dashboard is also at the upper hose nozzle, it's got only one wire.

watson10

I'll probably change out the 2 sensor / switches for the fans. But, I'm still not sure this will work because of my intermittent problem. I'm thinking if these are new, what else could cause these fans not to run? I read in my manual about relays, could these cause intermittent problems?

JimBlake

Sure, relays can cause intermittent problems. So can corroded wiring connections anywhere in the circuit...