Air Conditioning: low side too high. pressure switch?
#31
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From: Fake Virginia
MOAR update:
mag clutch clearance is within spec. On the small side. I'm sure it's fine.
no fuses are blown. related to the AC system.
I have continuity from the relay output to the compressor clutch, so that's good.
I can provide 12V to the clutch and it kicks the AC on and the low side pressure immediately drops below 40, so that's also good.
But for some reason, the relay is not powering the clutch.
Which may SEEM like a simple bad relay (of the other 3 wires, 2 measure 12V and one GND) except that when I swap the relays for the condenser fan and the ac clutch, the AC stays off and the fan runs. Whichever relay is on the fan side, the fan runs and the AC does not run.
The current to the AC clutch is not particularly high. I forget the number but it had a lot of zeroes in front of it.
Brainy is bringing me a spare relay to test.
More ideas?
mag clutch clearance is within spec. On the small side. I'm sure it's fine.
no fuses are blown. related to the AC system.
I have continuity from the relay output to the compressor clutch, so that's good.
I can provide 12V to the clutch and it kicks the AC on and the low side pressure immediately drops below 40, so that's also good.
But for some reason, the relay is not powering the clutch.
Which may SEEM like a simple bad relay (of the other 3 wires, 2 measure 12V and one GND) except that when I swap the relays for the condenser fan and the ac clutch, the AC stays off and the fan runs. Whichever relay is on the fan side, the fan runs and the AC does not run.
The current to the AC clutch is not particularly high. I forget the number but it had a lot of zeroes in front of it.
Brainy is bringing me a spare relay to test.
More ideas?
#37
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DEI liberal femininity
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From: Fake Virginia
OK megasquirt IS grounding the output. Until I connect it to the car.
Verified this on two separate outputs.
What would cause that? Bad relay? Remember the same relay works fine with the fan (and output on the megasquirt controlling the fan).
Verified this on two separate outputs.
What would cause that? Bad relay? Remember the same relay works fine with the fan (and output on the megasquirt controlling the fan).
#38
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DEI liberal femininity
iTrader: (8)
Joined: Jun 2005
Posts: 19,338
Total Cats: 574
From: Fake Virginia
not sure what happened but I fixed it/it fixed itself.
went back to original wiring i had used but with a new TIP120 and it works. it didn't last time I tried it that way, but what do I know?
went back to original wiring i had used but with a new TIP120 and it works. it didn't last time I tried it that way, but what do I know?
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