Mechanics

AIR CONDITIONING CLUTCH

2000 Honda Civic • 380,000 miles

Air condition clutch will not engage unless I jump 1 and 2 in relay. System is charged and have continuity at AC pressure switch. Condenser fan motor comes on when AC switch is turned on. Thought clutch gap may have been to much so bought new compressor and it also would not engage clutch unless I jumped 1 and 2 on compressor clutch relay. Also know that relay is good after switching it with compressor fan relay. Also spent four hours of tech time with Honda dealer and all he could say was it might be the computer but was not sure. I have 12 volts on terminal 17 of ECM-PCM and 4.6 volts on terminal 27 when I backprobe these at the computer. I have the Honda service manual and have done all steps in troubleshooting with no results. Have a new computer coming in a couple of days and will let you know if that solves this problem. Any information from you would be greatly appreciated! Robin
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Bobcat614
June 30, 2013.




What is voltage at AC low pressure switch?
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Docfixit
Jun 30, 2013.
A C pressure switch at two P connector # 1 terminal wire side is 12 volts to body ground.

Tiny
Bobcat614
Jun 30, 2013.
Both wires should have BATT voltage when switch is closed

Docfixit
Jul 1, 2013.
With terminal hooked back up to pressure switch and air condition switch in off position I have 12 volts to one and two terminals of pressure switch by method of backprobing.

Tiny
Bobcat614
Jul 3, 2013.
BOTH wires will have 12v switch closes at@45psi so jumper switch terminals if it works replace switch

Docfixit
Jul 3, 2013.
Disconnected terminal from switch and ran a jumper to both wires but the clutch did not engage although the condenser fan does run. I also did a test that my book talks about for checking thermostat. Have power on one and three on ac thermostat 3 P connector unhooked from thermostat and then reconnected it to thermostat and grounded middle terminal with no luck. It says to replace thermostat. Still waiting for my computer to show up. Maybe Friday.

Tiny
Bobcat614
Jul 3, 2013.
Sorry to be so long but had wait for two computers. Finally got the right one yesterday and I was very disappointed. Nothing changed and somehow I really didn't expect it to. So I went to the book again and decided to do a Continuty test between terminal 27 on the ECM/PCM and the pressure switch and found out the wire did not go all the way there. As I traced it behind the radiator and AC condenser I found two wires corroded (funny it was the blue and red to AC switch and black and red which I haven't decided where it goes ) cleaned them off and twisted them together. And you know what happened ( the seven hundred dollars I spent on a HONDA TECH and computer was a waste of money! ) The darn clutch kicked in and now I am the most satisfied person in the world. Thinking Monday I'm gonna go through this discovery in my tech's face and see if he has ever seen this before. It was funny none of the other six wires in this loom were touched! Thanks so much for all of your help! ROBIN

Tiny
Bobcat614
Jul 20, 2013.
Glad to hear but sorry for expensive PCM

Docfixit
Jul 21, 2013.

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