Has anybody ever had any problems with the override radiator fan control feature? Mine works, and I have been using it for the past 2-3 years. I occasionally notice my fan not kicking on because the radiator fan relay in the underhood fuse box is BURNT. I am using a Flex-A-Lite fan and have replaced the motor once. The company will be sending me another motor next week, because I want to make sure it is not the motor. I am thinking that it could possibly be Hondata or my ECU controlling the fan relay contact that the thermal fan switch normally controls.

These are some pictures of what is happening.





Once this happens, I obviously replace the relay with a new one and the problem is fixed for a short amount of time. A few months ago, readjusting and tightening the upper right connector in the fuse box terminal contact fixed the issue until last week when it happened again.

Has anyone seen such a thing?

 

Go through all of the wiring to make sure the wires are not damaged.
Perform an ohm test on all of the wiring and ground wires too.
Its likely that the fan was putting to large of a load on the wiring/relay/terminal to handle or you have a poor ground.
You may want to simply re-wire the fan on it's own external relay pulling power directly from the battery and using a good ground.

 

But why is the problem so intermittent? For example, the fan is working fine now. It will burn up randomly every few months.

I do not want to run an external relay because I want to keep all of my wiring stock.

How would I go about going through all of the wiring? I can't figure out how to open the back of the fuse box to see the wiring that goes to the relay sockets.

Lastly, I noticed you are in Tampa and I am in Gainesville. Would you be willing to help me out if I can't seem to do it? Seems you know exactly how to go about fixing this.

 

Buy a honda helms manual for your vehicle & start learning or pay someone to resolve the issue.

If you can't figure it out, give us a call to bring the vehicle in.

 

It may be dependent on another accessory that's shorting your fan circuit when it's engaged, or could just be an intermittent water leakage problem. I don't think you have the option of keeping stock wiring anymore since you're going to need to splice or replace something anyway. You can easily hide a relay, aftermarket doesn't always mean ugly.

 

No, just the plastic melted. The stock wiring is fine.
I figured out my problem. I was trying to, for all intents and purposes, run the fan all the time. The OEM wiring and relay is not meant for running the fan at all times, even if you set it up that through your ECU. I adjusted my S300 to turn on the fan at 180 degrees (using FANC), but that is too cool of a temperature. You can only use the FANC option as a backup if your thermoswitch fails, so it must be set higher than when your thermo switch normally turns on the fan. So for me setting the FANC to 200 degrees or greater is okay, that way my fan will still cycle on and off like it supposed to.

I did not realize, for almost 2 years, that the stock wiring and relay could not handle running the fan the whole time the car is on. I always though that it could handle a constant 10 A since the relay is rated at about 25 or 30 A.

 

Cast plastic rarely melts without consequence, if the circuit got that hot there's a good chance it also melted somewhere else in the harness.
OEM wiring is oversized for the calculated load, as most wiring is if it's in code. If it failed then it was defective or damaged.
I program many performance cars to switch on at 180 or 190 with no failures - especially in road races and autocross at high load and low airflow, if you wait for the fan switch you're already heating up too quickly and there's a warped head in your future.

 

Under the fan relay i had a wire on the side and it fell into it (never happened nefore)as shown in the first pic here. so the negative and postive touched and now the positive does not even turn on when i test it. 2 negatives and 2 positives. One positive the light turns on the tester but the other does not. No fan turns on.. help!!