I bought a 2006 Scion xb and it had a condenser leak. I replaced the condenser and it's dryer bag. Vacuumed and refilled. It worked intermittently. It's hard to tell when it will work, it's so random.
Evacuated and replaced expansion valve. It seemed to help with exit temperature, but the randoneas is back. I haven't been able to catch the random failure to check with gauges. Can bypass valve type compressors work randomly? I'm thinking intermittent pressure switch, but looking for more to troubleshoot and ideas on what else might be going on.
R
Snick
Random AC
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Snickers
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tbirdtbird
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Re: Random AC
First thing I would do is check clutch gap. If too big (ie over .020) the comp will come on randomly or not at all. This gap is important since the magnetism generated by the clutch coil can only carry just so far.
There are many threads on here about testing and adjusting clutch gaps. A search will prove effective
There are many threads on here about testing and adjusting clutch gaps. A search will prove effective
When considering your next auto A/C purchase, please consider the site that supports you: www.ACKits.com
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JohnHere
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Re: Random AC
I believe your Scion has an electronic control valve but no clutch. If so, the compressor is a variable-displacement unit driven directly by the engine. It's possible after 17 years that the control valve is malfunctioning, which could cause the problem you're experiencing. You'll have to have the refrigerant recovered before changing the valve, but the valve itself is relatively inexpensive.
Member – MACS (Mobile Air Climate Systems Association)
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Re: Random AC
Yes, variable control valve. If I'm doing that, should I replace the compressor too? I think it's original.
My wife noticed that the heat/cool damper control position (the one that goes from blue to red) seems to matter. Is there ever a switch or something hiding in there? I wouldn't think so, but who knows.
Thanks! That valve was going to be my next thing if I could ever get gauges on the system during a malfunction.
My wife noticed that the heat/cool damper control position (the one that goes from blue to red) seems to matter. Is there ever a switch or something hiding in there? I wouldn't think so, but who knows.
Thanks! That valve was going to be my next thing if I could ever get gauges on the system during a malfunction.
Re: Random AC
It wasn't that knob. It's the one that controls the dampers for which vents. if you move it a little off of the chest level one, it seems to work. She marked with with a sharpie. This doesn't seem like it would make the difference between working and not working unless there is a switch hiding in there. Any thoughts before I rip into the dash on a multi-hour wild goose chase?
Do pressure switches get intermittent and cause random AC ops?
R,
Snick
(by the way, this is an awesome forum! I'm glad I lucked into finding you guys)
Re: Random AC
Before you rip in to the control panel, spend the 20 bucks on a Mitchell DIY 1 subscription.
A one month subscription will give you access to the FSM. The wiring diagrams are all there. How to get the dash apart, little things like that.
May be some self test routines available too.
You get a month to read up on anything else you might need to fix. Best deal out there
A one month subscription will give you access to the FSM. The wiring diagrams are all there. How to get the dash apart, little things like that.
May be some self test routines available too.
You get a month to read up on anything else you might need to fix. Best deal out there