coronan Posted August 29, 2015 Share Posted August 29, 2015 This one is a little funky. I have an 82 chassis with a MPFI turbo ea81. turbo was not offered in 82. It cam available in '84. So for the hell of it lets say i have an 84. There is no power in the control circuit at the high and low pressure switches on the dryer. But i can engage the compressor by jumpering it to the battery. And idle goes up. I do not have a fuse in my fuse box for AC. Several switches must close in order for the compressor to come on. Where is the AC switch? Attached to vent control slider lever??? Where is temp switch? (attached to dial??) Where is Thermostat switch? Where is the condenser? Passenger side? Where is the AC relay? Thanks! Quote Link to comment Share on other sites More sharing options...
DaveT Posted August 29, 2015 Share Posted August 29, 2015 Don't know about that specific car, but the AC condenser is typically the heat exchanger placed in front of the radiator. Quote Link to comment Share on other sites More sharing options...
coronan Posted August 31, 2015 Author Share Posted August 31, 2015 OOPs, I not sure what i was thinking but lookin at the wire diagram again this morning: I see that the Condenser fuse must be good to close the the AC relay. Where is the condenser Fuse? Thanks! Quote Link to comment Share on other sites More sharing options...
coronan Posted September 1, 2015 Author Share Posted September 1, 2015 Here is the wire diag I'm using. As far as I can tell. If the blower is on the control circuit for the AC should have 12v. I am very curious where this Thermostat switch resides. Does it switch the positive side? I pulled the heater controls out of the dash yesterday. There are no wires on the temperature dial. Is there a switch somewhere on a damper? Quote Link to comment Share on other sites More sharing options...
wagonist Posted September 1, 2015 Share Posted September 1, 2015 Might not be a factory installed system. A/C in Aus was a dealer fit option, not factory fitted, so there is a separate (ugly) loom just draped around. The fuse for our system is just hanging off a wire near to the battery. There should be a factory looking switch somewhere on the dash near the fan speed and vent control that says "A/C". The thermostat will be attached to the box in behind the dash as it hangs a probe wire into the air flow from the fan on the way through the A?C box to the heater box. What do you mean by temp switch? These systems aren't that complicated. It only turns on/off at preset temps. You adjust the temp inside the cabin by using the heater box controls. Of course you can jump the compressor by attaching it to the battery, you've bypassed all of the safety features built in. Did you turn on the dash fan when you're trying to get the A/C to work? You can't just press the A/C button for it to go. It also needs a dash fan "on" signal. Quote Link to comment Share on other sites More sharing options...
coronan Posted September 3, 2015 Author Share Posted September 3, 2015 My Dash heater / AC controls look stock. Has the subaru emblem in the middle, and AC included in the Vent control. There are no electric switches in the heater controls for the AC... But there is a vacuum valve for max AC. The Thermo switch (thermostat is shown inline between the blower switch and AC relay. Wires for the Thermo Switch dissappear into loom tunning back to the steering column. I"m Still on the hunt for the 1. AC switch 2. Relay. Quote Link to comment Share on other sites More sharing options...
coronan Posted September 12, 2015 Author Share Posted September 12, 2015 Still looking for that silly AC switch... I've had busy weekends and evenings. I only get a chance to probe my ducting 10min at a time on breaks at work. Here is pic of the ducting in the center from the drives side. There is no switch here either. At this point i'm tempted to just put in my own switch and splice it into the high and low pressure switch. Quote Link to comment Share on other sites More sharing options...
coronan Posted September 12, 2015 Author Share Posted September 12, 2015 Can anyone confirm the physical locations of the items in red? And what those relays do? Thanks! Quote Link to comment Share on other sites More sharing options...
coronan Posted September 14, 2015 Author Share Posted September 14, 2015 Sneaky devil. But it's not hooked up. Looks like I'm pulling my own wire any how. Quote Link to comment Share on other sites More sharing options...
Loyale 2.7 Turbo Posted September 14, 2015 Share Posted September 14, 2015 I don't remember clearly right now, because it has passed long years since I serviced the wirings on any EA81 vehicle, but as far as I know, there are two relays in the engine's bay and one on the interior of the car, so there are three relays in total, for the A/C system. The one marked as Nº 11 and the one marked as Nº 26, are on the engine's bay, one of those is intended to power the electromagnetic Clutch on the A/C compressor, the other one is intended to power the Condenser's Fan, which is located Next to the Radiator's fan. The third relay is in the interior of the car, I believe it is the one marked as Nº 23 ...(as I told you, I'm not sure which one is which)... it works receiving the signal from the A/C switch, it is intended to Power the internal Fan for the A/C blower, and Also to send the power signal to the two relays outside, the ones on the engine's bay that I described before. And also there should be a Pressure sensor / switch on one of the A/C gas lines, it only allows the relays for the compressor's clutch and the Condenser's fan to get power and engage, if there is enough pressure of gas on the system; otherwise the compressor's clutch and the condenser's fan will never work. So, don't bypass their connections if they doesn't work and only the internal Blower works, you must verify the Gas pressure with a certified technician First, to be sure that there pressure sensor / switch is not preventing their functions due to a low pressure on the system, or due to a fail of itself... Kind Regards. Quote Link to comment Share on other sites More sharing options...
coronan Posted September 14, 2015 Author Share Posted September 14, 2015 Thanks for the outline on the relays. That confirms what i understood from the wire diagram What sent me digging into the dash was that i did not have any voltage coming into the high and low pressure switches on the drier in the engine bay. The micro switch that I believe triggers the beginning of the AC circuit is not hooked up and i don't see a place to plug it into the harness. I need to go back and study wire colors. Quote Link to comment Share on other sites More sharing options...
coronan Posted September 14, 2015 Author Share Posted September 14, 2015 (edited) I understand that most harness have some unused plugs for various options. I suspect some funny business in my wiring until proven other wise. What relays am I missing in the strut tower? First Pic: 1 of 3 relays is present. 1 has been bypassed. 5 pin connector has nothing near it to plug to. Sorry its out of focus, 2 pin connector with black and white wires. Nothing to plug to. 4 pin connector, Shaped like a relay connector but back by the firewall and pressure boost sensor Edited September 14, 2015 by coronan Quote Link to comment Share on other sites More sharing options...
coronan Posted September 14, 2015 Author Share Posted September 14, 2015 (edited) According to the wire colors.... All wires match the wire diagram in post #4. "NCA" wires are the same color as the just upstream. Output to the Compressor clutch is Green wire. Not sure What an FCID air valve is. Bueler? Per the Illustration in post #8: 11 = AC Relay [ on strut tower] Switches Sub fan control AND compressor clutch 25 = Condenser Fan Fuse, 20a [ behind air filter] 22 = Micro switch [on upper damper control for vent selection] [wire colors are Blue , Black ] 23 = ? 26 = ? Edited September 15, 2015 by coronan Quote Link to comment Share on other sites More sharing options...
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