Fastest klze swap?

for the a/c delete just leave the de-pin the harness if something think the a/c is running

and for me the first thing i connected was the a/c relay and i tested it

i had the p5 a/c relay wire ran to the kl ecu and everything else was hooked to the p5 ecu
and the kl ecu grounded the a/c relay which cause the a/c compressor to run so the ecu should think the a/c is on but idk how to make the ecu think the a/c is off
 
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this works some....how
when the a/c button is pushed and the blower motor is on the condenser fan kicks on so i wired the a/c relay's relay to the condenser fan relay so when the condenser fan kicks on the a/c clutch kicks on
 
looks good to me. These cross platform swaps generally end in odd wiring setups. Just a hint, write it all down for diagnostics later lol.
 
Well, picking this up again. Sorry for the absence. A lot has happened in the last year with other projects, including the car being wrecked a second time, me buying the car from Andy, and turning the Probe into a twin turbo project which took up most of the fall and winter. The P5 is now my daily and has been awesome. Anyway, the A/C was never completed and the sweaty season is now in full swing so it would be REALLY nice to get it going. I need to put the system under vacuum and check for leaks before I really do anything.
Im thinking the easiest way to do this will be to bring the P5 ecu back since it is set up for this system. Feed it power, grounds, RPM signal from the tach converter, and of course the A/C inputs and outputs. I would almost rather use the Probe ECU for all this but the A/C system on the Probe is a lot more complicated as far as multiple relays, extra pressure switches, etc. Sadly I threw away the P5 ECU connector a while back so I have to track another one down before I can start the wiring.
 
Got an ECU pigtail that I am streamlining for the compressor control. It wont be doing anything other than control the compressor and condenser fan.
Got a few questions if anyone knows. On a stock FS P5, if the key is in the run position and the engine is off, will pushing the A/C button cause the compressor clutch to engage? Im guessing it will have to see engine RPMs to engage but it would be a lot easier if it didnt. lol. Assuming is needs to see RPMs, I will have to try using the KL's 6 tooth crank pully and single tooth cam sensor. Is the stock FS cam sensor a hall sensor?
 
So doing some more exploring I found that the A/C system in the Protege is far simpler than I first thought.
The FS compressor will need a little work though. It needs to have the KL clutch and pulley swapped onto it since the FS runs one less rib in the A/C belt. It is pretty straight forward. Take the bolt out of the center of the pulley and remove the "pressure plate" from the center. Remove the snap ring and slide the pulley off. Remove the electromagnet via the 3 phillips screws. Re assemble the same way on the FS compressor. There may or may not be shims installed between the clutch "pressure plate" and the drive axle. Get the clearance small enough that the clutch doesnt drag but no so far that the rubber in the pressure plate isnt over stressed when the clutch is engaged.
The FS compressor will not bolt up directly to the KL A/C bracket. The upper left bolt is the only one that will line up the compressor properly to the belt. so an alternate bracket will need to be fabbed, which is not hard to do. I ordered a 6"x6"x3/8" aluminum plate off ebay for 15 bucks and should be here before next weekend.

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Completed FS compressor with KL clutch/pulley.
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This is the model A/C clutch im using.
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Should make some more progress next weekend. Want to have it going by the end of the month.
 
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The 4 cylinder compressor is now mounted up to the aluminum plate that I fabbed up. Spaced it away from the block for clearance and through bolted the compressor to the plate.
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Life has been hella crazy. I didnt get a chance to do much to the car last year due to other projects etc. I finally turned my attention to the A/C again and after replacing a leaking line and getting a hybrid pressure safety switch for testing safety, I have ice cold A/C. Its rigged on a toggle temporarily running through both high and low pressure safety switches as well as activating the fan for the time being. I will soon be wiring it up to be controlled my the stock KL computer as well as utilizing the stock P5 A/C amplifier for proper compressor cycling. Hopefully it wont be another year till the next update. lol.
 
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Cross posting my post from another thread:

Just to throw this out there pertaining to the A/C. Im doing my second KL swap into a P5 and making things as close to factory as possible, including the A/C. After a bunch of head scratching I figured out the best approach.
Note that this is using an OBDII Probe harness. OBDI may be slightly different.
First, you use the stock FS compressor by making a adaptor plate to mount the FS compressor to the KL block. Ive been using 3/8" thick aluminum plate with spacers. Remove the FS clutch from the compressor and replace it with the KL clutch. It swaps right on. Boom, no mixing and matching lines.
Next, run the A/C amplifier output wire to the A/C high pressure input on the KL ECU. This was labeled as the "A/C on" wire on the FS ECU. This will tell the ECU that the A/C button is pushed, activate the fans, and bump the idle speed to compensate for the extra load of the compressor.
Last, wire the A/C relay output on the KL ECU to a fused relay to feed power to the compressor. The output from the ECU is a ground.

Somewhat simplified explanation on how it works: The KL a/c system uses high pressure and low pressure switches in the system to cycle the compressor. The low pressure switch prevents compressor damage from too low levels of refrigerant. The high pressure switch shuts down the compressor when pressure is too great, which would eventually freeze the evaporator core. In the P5 system, its simpler. It still uses the low pressure sensor for the same function, however it is used in conjunction with an A/C amplifier. The amplifier uses a temperature probe to monitor how cold the evaporator is getting, and will cut off the compressor to keep it from freezing up, then cut the compressor back on once the evaporator is above freezing. The output of the amplifier goes through the low pressure switch, so its essentially two sensors in one. The output of this goes to the KL ecu through the high pressure input to tell it to turn on the fans, compressor, and bump up the idle. The KL ecu will also shut off the compressor under wide open throttle.
 
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