Mend > Cars

A/C PRESSURE SWITCH CONNECTOR?

I HAVE JUST REPLACED THE A/C COMPRESSOR IN MY 1999 FORD ESCORT BECAUSE THE OLD ONE WOULD NOT TURN ON -IT STILL WONT COME ON -EVERYTHING WORKS -THE ONLY WAY IT COMES ON IS IF I CONNECT TERMINALS OF THE CONNECTOR PLUG TO THE BATTERY THEN IT WORKS FINE(TEST ONLY)IT WONT COME ON WITH THE SWITCH-JUMPED CONNECTOR PLUG NO POWER EVEN WITH THE A/C SWITCH ON HELP!

pete_mascorro@yahoo.com
September 2005

Ford Ford Escort Vehicles, Cars Switch Replaced Ford

Hi Pete,
I have a 2001 ZX2 and my AC operation is intermittent with the compressor clutch sometimes working, sometimes not. I have since searched the 'net and have also obtained a set of Ford wiring diagrams for this car. Based on everything I have learned your pronlem (an mine) has nothing to do with the mechanical/refrigerant part of the AC system, but with the electrical control system. The problem seems to lie in a device Ford calls a 'Constant Control Relay Module' or CCRM for short. It is located in the engine compartment under the air filter housing. From what I can gather from various places on the 'net the failure of the CCRM and hence the intermittent/non operation of the AC is VERY COMMON on 1999+ Ford Escorts and ZX2s (and other Fords). A small relay inside the CCRM (of which there are many) fails. This relay - which itself is controlled my the main vehicle computer (PCM) - essentially connects the AC compressor clutch to 12V power. A new CCRM from Ford will set you back over $200. There are other workarounds that have been used. Email me if you want more technical info.

Paul

paul78zephyr@verizon.net

Paul
September 2005