beegyboy22

I recently had to replace the radiator and thermostat in my 1996 Honda Civic due to an overheating issue. I replaced it only to find that the fan was not turning on and the engine was still overheating. The fan motor itself is operational, it just doesn't receive the signal to turn on automatically. I also replaced the 12v relay so that can't be the problem either. My next guess was that the thermo switch was not turning on, so I warmed the engine up to the point where the fan should have kicked on and I measured the voltage that the switch was putting out. It was reading about 0.020 Volts. What I'm wondering is that the normal Voltage for the switch to put out? If not, what could be the problem? Thanks.

Wankenstein

You can wire the radiator fan to run constantly in the meantime: https://honda-tech.com/forums/honda-...rking-2580655/

(copied and pasted) "The fan switch (thermoswitch) is located on the thermostat housing. Unplug the 2P connector and install a jumper wire between the two terminals of this connector. The fan should now run continuously when the key is in ON(II). If so, replace the switch."

ezone

Unplug the connector for the fan temp switch.
Use a paper clip to jumper the two terminals inside it.
Turn key on. Does fan run?

Wankenstein

OP...losing coolant in radiator since overheats?
Overheating can lead to a headgasket breach.

beegyboy22

Yes. I tested to make sure it wasn't the wiring. The fan receives the signal and turns on like it's supposed to. Could my problem be incorrect thermostat placement?

beegyboy22

I think it may be burning a little coolant, but I just drove around and after the engine began to overheat I checked the coolant level and it was right where I left it.

ezone

What do you see/hear/feel/smell that makes you say it's overheating??

What is the actual temperature measured at the hose side of the thermostat housing, at the upper radiator tank or hose, and as read by the PCM in a live operating datalist?


How much time does it take to go from stone cold engine to overheated?

Does liquid circulate in the radiator while the engine is running?


When you took the radiator out of the box to install it, did you make sure the shipping caps or plugs were removed before installing the hoses?

I dunno, didn't you install it correctly?