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Not on all the time Posted by Ari [Email]  (#2847) [Profile/Gallery]
(more from Ari) on Fri, 1 May 2009 20:20:20
In Reply to: Re: a/c troubleshooting, PhilM, Fri, 1 May 2009 18:30:29 Members do not see ads below this line. - Help Keep This Site Online - Signup |
The 12 volts to the clutch cycles on and off. When 12 volts hits the clutch, it pulls in, and the compressor spins.
Do you have ACC or manual (knobs?) If you have manual temperature control, make sure the fan speed is NOT set to "0", AND make sure your cabin fan is working properly. Namely, the fan speed only works with the knob set to Hi.
If you have manual temperature controls, the fan speed selector sends 12V to the AC push button, and then on to the pressure switch. If you have ACC, the ACC sends 12 volts to the pressure switch. From the pressure switch, the 12V goes to the freeze-up switch, then to the AC relay coil. That pulls in the AC relay, which then sends 12 volts to the Clutch. If the pressure switch or the freeze-up switch is open, the relay won't pull in, and the clutch won't engage.
A quick way to determine if you have a low pressure issue is to simply check the resistance of the pressure switch. With the car off, find the receiver/dryer (down low on the right side of the engine compartment) - the pressure switch is mounted on the side. Find the 4 wire connector. Disconnect the connector, and measure the resistance of the switch at pins 1 and 2. Those correspond to the green/white and yellow/white wires. This is engine off. If you read an open circuit, the pressure is low or the pressure switch is bad - my money is on low pressure.
What climate control system do you have - ACC or manual?
If you check the pressure switch and it reads closed (less than a couple of ohms, as compared to an open circuit), send me an email, and I can send you a schematic.
posted by 192.249.4...
, Fri, 1 May 2009 20:20:20 <-- Viewing This Message, Sat, 2 May 2009 05:26:24, Sun, 3 May 2009 06:46:19
, Sun, 3 May 2009 12:26:59, Mon, 4 May 2009 06:39:30
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