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We got a 98 Ford Escort SE wagon that had an A/C problem which looked like the CCRM, so we replaced it. The car now has a brand new CCRM and the A/C compressor runs. Here's the thing though, the A/C compressor DOES NOT engage in the A/C or MAX A/C positions. But, it does engage in the Dash Vent, OFF, Floor vent and defrost positions. If the compressor is engaged in, say, the dash vent position and I switch it to the A/C position, the compressor runs for a few seconds and shuts off.

The car belonged to my daughter's father in law who gave it to us for one of our younger daughters since he could no longer drive. My older daughter drove the car a few times in the last few months her father in law still had it and she said this is haw the A/C always acted as far as she knew. She says the A/C had always been messed up. So the CCRM replacement didn't start this problem. The father in law (now deceased) had the car since new so it follows that the A/C worked correctly at one time.

Any ideas where to look? Maybe the switch in the dashboard? It is vacuum or electrically operated?

  • "SE wagon " ?? we need more than this to identify the car. – Moab Jul 3 '18 at 21:08
  • It's vacuum operated vents. With the switch in either ac position do you have power at the ac low pressure switch? Maybe try unplugging the control head and powering the line to the switch while watching a scantool for an ac request. – Ben Jul 3 '18 at 21:23
  • Sorry, it's a 1998 Ford Escort SE Wagon. 2.0 L – Jason Fox Jul 4 '18 at 16:29
  • Here's what a fellow on the FEOA forum posted for me, "The HVAC selector switch is both a vacuum switch for the various vent controls, and an electrical switch for the blower motor and A/C compressor. If you remove the radio/HVAC panel using an inexpensive set of U-shaped wire tools (after disconnecting the temp control cable to the right of the gas pedal), you'll see a an electrical connector for HVAC. The white wire on pin 4 provides A/C power from the A/C fuse. The orange wire (or orange w/green stripe on the switch side) on pin 3 switches current to the A/C system. – Jason Fox Jul 4 '18 at 16:30
  • Continued: If you unplug the connector, test the switch side for continuity between pins 3 and 4 with a DVM in each of the 8 positions. Continuity = On, Open = Off. You probably have a bad switch. Get a replacement OEM radio/HVAC from the junkyard (97-02) and swap it in. (Easier than trying to replace just the switch.) If the switch tests out ok, then there's a wiring harness problem. – Jason Fox Jul 4 '18 at 16:31
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Problem turned out to be the wrong CCRM. I used a CCRM for a US built Escort and mine was made in Mexico. For some reason they are different. Seems to only affect the A/C. Apparently, the CCRM had been replaced with the wrong one a number of years ago and they just lived with it. So, when I ordered a replacement, I got the wrong part, too.

Since I could not return the CCRM, the solution was to build a little module with an interposing relay to invert the "logic". This required that I separate the connectors at the HVAC switch and make up leads for the blower for pins 1 & 2 of the connector and then wire in my module on pins 3 & 4. The little relay module then got stuck to the bottom of the radio with double sided tape.

The A/C now works correctly and will officially freeze meat.

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