Checking to see if your Radiator Fan is working

[WOW_FCTR]

[I stole this from a Mike in AZ post]

Each of us should check to see that our main fan is working periodically. This is especially necessary for those who have my Auxiliary Fan Kit installed, as it provides enough airflow that it may mask a Main Fan failure.

Start your engine and let it warm up. The engine MUST BE above 185 before starting this test. There is a software lockout on the main cooling fan operation below 185.

With a "warm" engine, turn your HVAC Blower to 3 (middle of the road number) and select the A/C "On" button. This should kick on the compressor. When the system pressures get up to a "normal" operating range, the main cooling fan will turn on to "Low" speed. There is almost no fan noise in this condition, so you will need to visually verify that the fan is running. If it is running, the fan motor and the 1 ohm resistor (buried in the fan motor) are both good. Once you have seen this, select the "Recirculate" button. This will cause the A/C pressures to run at a higher level. When the computer sees a high enough pressure split on the A/C system, it will command the fan to "High" speed. You may not go to high speed right away and you may not stay at high speed. There are a lot of variables (Outside Air Temp, A/C freon level, re-ingestion of hot engine compartment air through the condenser and also through the evaporator, etc, etc, etc.....) that will determine the A/C commanded operation...... You will have to try it yourself and get a feel for it.

Assuming that your 60 amp Cooling Fan fuse has not failed (this happens occasionally, but usually because the fan has failed) and the computer has not had an internal failure (Highly improbable)........ If the fan is not running on "Low" speed, your problem could be a bad fan motor, bad 1 ohm resistor, bad wire to the fan or a bad low speed relay. If your fan operates OK on low speed and does not run on high, you have either a high speed relay failure or a bad wire to the fan.

At any rate, I seriously recommend that every SSR owner check his fan operation regularly. Kinda like checking the oil, water and tire pressure..... How often is up to the individual.....

A special note.... I believe there is a software glitch in the computers that will run the compressor if you select "Recirculate", even if the A/C switch is selected off. I think it is also independent of the HVAC blower setting..... I'm not sure... Go experiment for yourself. There is a little software boo-boo in there somewhere. Just another little quirk of the SSR.....

Hope this helps....

Mike