Mishako129

My cooling fans are not turning on even with the a/c switched on and blowing. Before then just my radiator fan would come on with the a/c switch but now non of them come on. I tried jumping the thermo switch on the cylinder head with a paper clip but nothing happened, they both wont turn on. I think that rules on the switch as being a problem.

I just replaced the condenser fan with a known working one. It was just last week I diagnosed it as being a problem. I tested the relay under the fuse box and was tested to be good, and the relays by the pw steering pump were tested to be good. Now for some reason (maybe cause it was really rainy and wet outside), non of them come on and I cant figure out why.


Its a 91' accord btw.

NZXTInerTia

You're supposed to jump the plugs on the inlet and outlet coolant sensors. Currently the one at the thermostat does nothing, but the one at the front of the block turns the main fan on. An issue I need to take care of as summer is approaching quickly.

The condenser fan relays go out all the time, take the compressor relay and swap them and see if it works.

Mishako129

I did jump the plugs for both of the coolant sensors and nothing happened. I also switched the fan relays (the ones near the pw steering pump) and nothing happened. The fuses were checked as well. Isnt there a switch underneat the dash that can be checked?

Mishako129

I tested the voltage for the radiator and condenser fan. There were no readings at all. What I have also done to diagnose this was switch the fuses in the fuse box, the power window with the fan one, it did nothing to the power window or the fan. I also checked for blown fuses, there were non. I am going to now check the relays by the power steering pump. I don't really know how to test them though, last time I switched them around, the condensor fan with the rad. fan but that did nothing. Now no fan's work and switching them will not be a valid test. Should I hook a volt meter to it and measure the ohms?


I checked the motor for the radiator fan, it worked fine. I already ordered new fan relays on ebay for 12.00, these are the ones,





I am 75% sure its the relays but I want to be 100%. To refresh your memory as to what is wrong, the problem I am having is the fans do NOT come on when I turn the AC on, they SHOULD come on. Isn't it the relays (things I bought) that tell the fans to come on when I have the AC on? If not is it possible I have a wire short somewhere?
How do I go about testing the relays if they work?

Falcro

To find a short in your wiring, get a factory diagram and a beer...read the diagram tracing out the circuit you want to test, use a yellow (or color that suits you) highlighter to note the connections....drink your beer... not get our your VOM and grab another beer. turn on the VOM and check it to make sure everything is functioning. drink your beer. Now grab another beer...check for voltage and continuity on all the main connections with the VOM....drink your beer... turn off the VOM...grab another beer. carefully wrap up the wires for your VOM so they are ready for storage then put the VOM away....get out the diagram you highlighted before and mark off the connections that you tested. Drink your beer. put the diagram on the front seat so you can see it...grab another beer. now this is the most important part so pay close attention.... Find a buddy or make a new one that is fluent in automotive electrical give him the rest of your beer (the ones in the case not the one in your hand lol) and have him fix it for you... sorry guys I know this didn't help you solve your problem, I just had to say this here. I can build an engine that will scare you, but electricity and I part company at the switch that turns it on/off after that it is someone elses problem.

holmesnmanny

To test the relay you apply power to two of the pins and it completes the circuit on the other two as the battery voltage on the other two magnetizes the other side straight, which completes the circuit. Just use a 9v battery and a couple test leads and use a multimeter to check continuity of the other two.

NZXTInerTia

And a beer for Falcro.

Lost Again

Based upon "other information" the OP posted......Thermo A, on the t-stat housing where the lower hose connects, is bad.

Lost Again

I didn't think you were old enough yet?