Having a problem with the vehicle overheating, primarily when the A/C is on, it's hot outside, and I become stopped in traffic after travelling some distance. I can watch the needle go up. Obviously, turning off the A/C stops it from going up and turning on the heat expedites it in going down.

It seems like the radiator fan is not coming on, but I have jumpered it and verified that it works okay. I also understand that the thermostat could be malfunctioning, and that is on the list of things to consider.

Three questions, though:

1. When exactly should the radiator fan come on. All the time? Or only when the engine reaches a certain temperature, and what regulates that?

2. If I'm not mistaken, the relays for the radiator (cooling) fan and power windows are identical (same Mitsuba part number). Can I swap them and either try my windows or see if the radiator fan comes on as a test?

3. I cannot seem to find the radiator fan switch using a diagram in a Haynes repair manual that I have. I know what it should look like and have found the A/C switch on the left end (looking at it from the front of the vehicle) of the block. It's green. Any help on that?

Thanks again in advance.
John

 

Engine fan is independ, the only way is to listen carefully when you driving(mostly local), or drive hard and pull over and see if it will work. honda's fan are pretty powerfully loud so you wouldnt have problem hearing it.

 

well first of all check if u got enough coolant.
check if the fan motor works.
conect the battery to the fan plug and see what happens.

the swich that u are looking for is near the thermostat. its green >>> u won't miss it.

turn the cold ac on and see if both fans are working.>>> they should

then check for leaking hozes.
if everything is ok then u might have some air in the system.

 

The most likely solution to your problem is a radiator flush...it's possible that your radiator just has gunk and deposits and stuff making it difficult for your coolant to flow properly. Go to Autozone or some similar parts store and buy a $5 radiator flush and some coolant to replace what you've got....it'll take about an hour (if you count the time you let the car run with the flush solution in it)....if that doesn't work, then try the thermostat...THEN the radiator fan...

 

Here's what I found out:

The relays are identical and when I swapped them, my power windows stopped working and my radiator fan started right up. Problem isolated.

BTW: If I am not mistaken, the green switch near the thermostat is the A/C switch - not the correct one. The radiator fan switch is more to the left and rearward, not immediately visible, and not where I expected it, but definitely in the area Haynes indicated (I think they pulled some wires out of the way when they photographed it).

Thanks for the help!
John

 

yeah its right on the thermostat. they pulled the distributor wires so u can see the swich better. if u move the thermostat housing then u will see the whole swich. (at least in my 90 accord)

 

check the fan switch