[zerioustt]

heres some info from a ford website..id look for more but im lazy

Back in 1986, with the introduction of the Ford Taurus and Mercury Sable, Ford Motor Co. started using a little black box to control numerous functions including air conditioning, cooling fans, fuel pump operation and powering up the powertrain control module (PCM).

This black box has had numerous names over the years including integrated relay control module (IRCM), constant control relay module (CCRM) and variable relay control module (VRCM). It has also found its way into numerous other models including the Thunderbird/Cougar, Mustang, Windstar, Mark VIII and the Escort/Tracer.

For many years, Ford was very consistent in the way it controlled the wide open throttle (WOT) AC relay inside that box. Traditionally, the WOT AC relay was a normally closed relay. If the PCM detected a condition that required turning the AC compressor off (wide open throttle, excessive engine temperature, or no AC 'on' input to the PCM), it would ground pin 22 of the module. This would open the contacts of the relay, causing the AC compressor to lose power and turn off.