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Hoping this is the correct subforum for this. I recently bought my son his first car, 2006 Civic EX coupe. Got a pretty good deal as the AC was inop(or so I thought). Haven’t been able to figure it out so here I am. When the car is initially turned on, and the AC is turned on, the AC will run for about 5-10 seconds then shut off. Both fans do come on. I have replaced the compressor, the expansion valve, high pressure switch, and relay. Refrigerant level is approximately 15 ounces, put in with a Mahle automatic machine at work. I’m at a loss of what else to check as everything has been replaced. The controls in the dash do pass the self test. After numerous searches I have yet to find a post with this issue of running great, then shutting itself down. Any help would be appreciated!

 
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When the shuts off, do the fans keep running? Check the compressor relay?

 
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The fans do not keep running. Followed a troubleshooting thread by ezone to test the relay socket, it seems to be functioning properly. 1 pin is a constant 12v, one pin has continuity with ground, one pin has 12v when the key is on, and the last pin appears to receive signal. Relay was replaced with a new one just for piece of mind and swapping it provides no change. I do hear a click, as if a relay was activated, when the system shuts down, but it is not the compressor or fan relays.

 
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If the relay were failing the fans would keep running after the compressor stopped. I would recommend checking the system pressure using a set of gauges. Could also be an issue with the PCM or HVAC controller.

 
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I was finally able to check the pressures. At approximately 95 degrees ambient air temp, low pressure is at 105psi, high pressure is at 120psi. While running, the low pressure will drop to about 40psi, high pressure goes to 140psi. It does have code p0533 that keeps coming back when I clear using thinkdiag.

 
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Troubleshooting steps for that fault.

http://civic.hondafitjazz.com/A00/HT...533FAAT00.HTML

 
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Been working through that setup, is there a way to jump the scs line without hds? Everything passes up to that point. Figured I might be able to disconnect the battery for an extended length of time seeing as it’s just a continuity check

 
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Struggling to find specifics. Do you see an orange wire in the OBD connector? If so, try jumping that to ground. Should be the SCS line.

 
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Just wanted to provide an update, it seems a lot of people don’t update with what the fix was. I was able to do the continuity test between the pressure switch and ECM, ended up finding an open wire. Started at the sensor and traced it back to where the harness passes by the right fender. I am assuming the car may have been in a front end incident at one point. Once I peeled the wire loom off, I ended up finding a couple of wires that had been cut. Two went to the abs module, and one was the green wire for the pressure switch. Re-soldered and heat shrinks everything and put some more robust wire loom on to protect it a little better and the AC is all fixed up and working great. Thanks for all the help everyone!

 
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We greatly appreciate you updating the thread!