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Discussion Starter · #1 ·
1994 Passport...I checked fuses and replace the AC relay but still the compressor clutch is not engaging...any ideas?

The symptom at first was that the there is not cold air coming thru the vents, I thought it was low on refrigerant, that is how I finally looked at the compressor's clutch and notice it's not turning when the ac switch is on.

Thanks in advance for your help.
 

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This sounds like the fluid has all leaked out.

IF the system gets too low on fluid the compressor will not come on at all. Go get yourself two cans of fluid at any parts store (about the size of a can of WD-40) making sure one comes with the filler hose and connector. Make sure that you get the correct type for your vehicle. Fill the unit until you see bubbles in the glass eye on top of the dryer (round thing in front of radiator behind grill) and check to see if it comes on. There are two connectors in the plumbing. One is on the passenger side near the firewall and has a blue cap. The other is on the drivers side. The connector on the filler hose will only fit the connector on the passenger side.

If it comes on and shows bubbles after one or both of the cans (it shouldn't take a full two cans) have it checked for leaks. If it doesn't come on at all and your sure all the electrical systems are good, you'll probably need a new compressor.
 

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Discussion Starter · #3 ·
I got the two cans of r134 and the filler hose that comes with a gauge.

Now to refill the system, since the AC compressor clutch is not engaging...will the r134 travel through the system without them?

Or do I need to jump the clutch directly to the battery ( or jump the relay, or low pressure switch) so it can suck the r134? At least enough to were the pressure sensor is "happy".
 

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Jumper the low pressure switch and see if it works and you get cold air. If the compressor works and no cold air, then you are probably low on freon. You can search the site for instructions on charging.

One last thing, don't leave the AC compressor running long if the jumper works. With it low on freon the oil will not circulate, causing the compressor to lock up.
 

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Discussion Starter · #5 ·
Thanks for the pointers. I will jump the low pressure switch and hope it starts, summers in Tucson without AC are no fun at all.

I'll post my results...

PS: Is the low pressure switch mounted on the compressor itself or the accumulator on our vehicles, or elsewhere? I'll dig out the diagrams and look for it.

OT: Kinda late now, but after doing some research, it looks like the pressure switch is mounted to the condenser, which is located next to the radiator, on the driver's side. Item number 23 on link below...

http://www.hondaautomotiveparts.com/aut ... ER+%281%29
 

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If its going to work, you should not need to jump the switches. The fluid will travel through the lines enough to let the switch activate. The fluid has to pass the switch to get to the compressor.
 

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Discussion Starter · #7 ·
I jumped the pressure switch and it worked. Just put a paper clip as a jumper between the Brown wire and Green/Blue wire. It's a triple pressure switch so there are 4 wires going to it. The other two that I didn't bother with are light Green/Yellow and Pink/White.

I did have to remove the grill to have better access to it, just takes a minute and a screwdriver.

I just ran it for a few seconds with the jumper while charging the AC. Then I plugged the sensor back and the compressor ran by itself, made the switch happy, then finished charging the system. Used two cans of r134.

Now I am just going to monitor the pressure for the next few days or weeks and hope it holds and I don't have a leak.

johnnie59, I had a can of r134 yesterday, and old one that still had freon, I tried charging it it that way, without jumping the switch and the compressor didn't kick in. Maybe that old can was plugged or something, so I tried the jumper today just in case.

Thanks firstamigo, johnnie59 for your help :D . You guys pointed me on the right direction and hope this thread helps someone else.
 
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