[joeelliottshin]

Hello. I have a 1992 Honda Accord EX, but recently I noticed that the cooling fan does not turn on when the car overheats. The cooling fan and the condenser fan works when the AC is on (hence, I know the fan is not the problem here).

Given the above mentioned problem, so far, I (1) drained the radiator; (2) replaced the thermostat; (3) replaced the coolant temperature sensor.

Nevertheless, the cooling fan does not seem to turn on when the engine overheats. I am thinking of replacing the 'cooling fan switch', but before I do so, I would like to know if there's any good advise as to why the cooling fan might not be turning on.

Thank you all in advance!

[joeelliottshin]

Hello. I have a 1992 Honda Accord EX, but recently I noticed that the cooling fan does not turn on when the car overheats. The cooling fan and the condenser fan works when the AC is on (hence, I know the fan is not the problem here).

Given the above mentioned problem, so far, I (1) drained the radiator; (2) replaced the thermostat; (3) replaced the coolant temperature sensor.

Nevertheless, the cooling fan does not seem to turn on when the engine overheats. I am thinking of replacing the 'cooling fan switch', but before I do so, I would like to know if there's any good advise as to why the cooling fan might not be turning on.

FYI, I have also swapped the 'cooling fan relay' and the 'power window relay', and the cooling fan rolls when the AC is on (hence, I believe the relay is not the issue). Any kind of comment/advise will be greatly appreciated.

Thank you all in advance!

[TxGreaseMonkey]

. Ensure that you have properly purged air from the cooling system, when you refilled it, by opening the bleeder bolt. Close it, after coolant starts to come out. The link below should help:

https://www.askmehelpdesk.com/cars-t...tml#post235973

. Replace the Engine Coolant Temperature (ECT) SWITCH, which is located on the thermostat cover. It has two wires going to it. This link should help you properly test it:

https://www.askmehelpdesk.com/cars-t...ml#post1642158

A major air pocket, bad ECT Switch, blown fuse, or bad fan relay could prevent the fan from coming on. My bet is that the ECT Switch has failed. Also, not using the proper antifreeze and distilled water can cause phosphate scale to develop on the ECT Switch.

[joeelliottshin]

Thank you for your prompt reply. Your advise seems to be in check with mine. I'll replace the 'cooling fan switch' - but the problem is, when I took a look under the hood, I actually saw 3 switches (one of them being the coolant sensor). The coolant sensor I know where it is, but there was a switch attached to the thermostat housing, and there was another switch located nearby the front of the cylinder...

Hence, I do not know which one is the 'cooling fan switch'. Could you please advise further as to the location of the cooling fan switch and the other 'switch' and its function relative to the car? Is the cooling fan switch attached to the thermostat housing, or is it located in front-left of the cylinder? Thank you very much.

. Ensure that you have properly purged air from the cooling system, when you refilled it, by opening the bleeder bolt. Close it, after coolant starts to come out. The link below should help:

https://www.askmehelpdesk.com/cars-t...tml#post235973

. Replace the Engine Coolant Temperature (ECT) SWITCH, which is located on the thermostat cover. It has two wires going to it. This link should help you properly test it:

https://www.askmehelpdesk.com/cars-t...ml#post1642158

A major air pocket, bad ECT Switch, blown fuse, or bad fan relay could prevent the fan from coming on. My bet is that the ECT Switch has failed. Also, not using the proper antifreeze and distilled water can cause phosphate scale to develop on the ECT Switch.

[TxGreaseMonkey]

The Engine Coolant Temperature (ECT) Switch is located on the thermostat cover.

[joeelliottshin]

Okay... So let's try to summarize now... Thank you again for your prompt replies, TxGreaseMonkey!

I know where the 'coolant sensor (TW sensor)' is...
Based on your reply, I believe I now know where the 'cooling fan switch' is... (on the thermostat cover/housing)
But are the 'cooling fan switch' and 'engine coolant temperature switch (ECT switch) the same thing?
Furthermore, there another switch... located in the front left side of the cylinder cover... what is that and what is it's function, do you know?
Thank you again in advance!

The Engine Coolant Temperature (ECT) Switch is located on the thermostat cover.

[TxGreaseMonkey]

Yes, they are the same switch--mine is the correct term, however.

[joeelliottshin]

And the Engine Coolant Temperature ECT Switch is the one attached to the thermostat housing; and the thermostat housing is the cover that surrounds/covers the thermostat, correct?

Thank you so much, TxGreaseMonkey, for everything. I will definitely let you know if the car is fixed!

Best regards,

Joeshin

Yes, they are the same switch--mine is the correct term, however.

[TxGreaseMonkey]

Yes