My 95 Civic EX began over heating yesterday and noticed the radiator fan not coming on. I ran wires directly from the radiator cooling fan motor to the batteries and the fan works fine. Therefore, it is somehow not being triggered on when the coolant gets hot.

Theupper radiator hose gets hot indicating the thermostat is open. The cooling fan fuse is fine.

I assume it is the cooling fan relayor the engine coolant temperature switch. Does this sound about right? If so, can I buy after market or do I need to get these from a Honda Dealer?

Thanks in advance!

-Garon

 

Start by checking the switch. It's easy to check the switch by bypassing it. Find the switch on the thermostat cover (where the LOWER radiator hose meets the engine) and unplug it. Jumper the two wires in the plug. Turn the key on and the fan should run even with the engine cold. If it does, replace the switch. If not, check the fuse and the relay.

 

Thanks! Are you sure it is by the LOWER radiator hose and not the UPPER hose? Isn't it next to the thermostat, which I believe is next to to the upper hose?

And what are your thoughts on an aftermarket switch from a parts store (versus the Honda dealer)?

 

Yes on a Civic and many Japanese cars the thermostat is at the lower hose connection. Works the same way, but it stops coolant from leaving the radiator instead of stopping it from entering it.

It may be a bad thermostat if it overheats under all conditions. Finding you can get the fan to run constantly by jumping the switch you may want to test it in that condition to see if having the fan running will indeed stop the overheating before buying a switch.

Aftermarket switch will be fine. Probably comes from the same place that Honda buys theirs from.