I have a 1998 Honda Civic Dx with a cooling problem that just started up. When I am idling the temperature gauge will start to rise and on the highway the gauge stay at normal operating temperature. I have 2 fans in my car and the radiator fan is not coming on when I turn the a/c on. So this leaves my to suspect that I have something wrong with that fan. I then opened up the fan connector and I clamped a wire from one of the male pins to the negative terminal of the battery, and another wire to the positive terminal and the fan turns on. (Jumping the fan). The fuse for the cooling fan is still good under the hood. So how can i check the rely. thermo switch, wires for a short, or anything else that it could be? Diagrams or pictures what to look for would be great also, thanks all.

 

If you jumped the fan switch connector with a wire and the fan turns on, the relay is good. It's your fan switch that screws in to the head is the culprit.

 

So I just touched a wire from the negative terminal of the battery to one the of the female connections of the radiator fan switch connector and the fan ran. I will replace the radiator fan switch and report. thanks

 

Just replaced the radiator fan switch and when i turn the a/c on the radiator fan is still not coming on...any other thoughts/tests i can do?

 

It's not supposed to. Unlike most cars, on these Civics the radiator and A/C are separate systems.

 

Yes only one fan should come on with the A/C. Just let your car idle and watch your temp gauge.

 

just had this issue today,replaced the fan switch as fan worked when the switch is jumped.fan turns on at 210 degrees,stays on for couple of minutes and goes off when temp is below 210.you may have to leave it in drive with e-brake set(automatic) to approximate being in traffic.

 

Problem solved, it was the fan switch, thank you all.