2002 Civic AC Mystery..
07-21-2016
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2002 Civic AC Mystery..
I have a 2002 Honda Civic Ex (4 door, automatic) still going strong after 200,000+ miles, for the most part..
Just recently my AC decided to stop working (Only the AC), after checking the fuses, going to the mechanic there seemed to be nothing that could revive the AC. The Freon was checked, compressor as well as the wiring. Per my mechanic one of the last options was to check the MPCU. With it nearing winter I opted to wait as I would only need the heat for several months. So after the temperature outside started to reach the high 90's and the humidity over 80% I decided it's time to try and figure this out again.
1 New multiplex Control Unit later the issue is the same, in fact the only way I can make the ac even work is to connect a ground wire to the frame and wal-la ac! But no Heat, seemed like an okay tradeoff for the time being. Main issue with doing this is that now the AC is on all the time and isn't getting the computer information of what temperature to stay at so it's basically on artic freeze anytime my car is on. Like I said before not a huge deal due to the outside temp being so miserable.
So with all this said and the AC on all the time it gets so cold that you pop the hood and the pipes are literally white with frost. Not to mention it now snows in my car as well. (I'm not joking..) Driving while snow hits you in the face in the middle of summer can be a bit distracting let alone hard to explain if you get pulled over..
My mechanic is at a loss and can only recommend taking it to the dealer to have them figure it out. At this last time when he replaced the whole MPCU now my radio doesn't work. I've checked the fuses (under the hood/back of the radio & new control unit), wiring etc. Nothing is out of place. There are no other issues at this point, windows/automatic door locks/overhead lights all work.
I was curious if it could be as simple as the actual button on the dash that "Turns on the AC Unit" as for the radio I'm at a loss and will have to give in and take it somewhere else to have that looked at. Does anyone have any thoughts or maybe had similar situations that could offer some help?
Just recently my AC decided to stop working (Only the AC), after checking the fuses, going to the mechanic there seemed to be nothing that could revive the AC. The Freon was checked, compressor as well as the wiring. Per my mechanic one of the last options was to check the MPCU. With it nearing winter I opted to wait as I would only need the heat for several months. So after the temperature outside started to reach the high 90's and the humidity over 80% I decided it's time to try and figure this out again.
1 New multiplex Control Unit later the issue is the same, in fact the only way I can make the ac even work is to connect a ground wire to the frame and wal-la ac! But no Heat, seemed like an okay tradeoff for the time being. Main issue with doing this is that now the AC is on all the time and isn't getting the computer information of what temperature to stay at so it's basically on artic freeze anytime my car is on. Like I said before not a huge deal due to the outside temp being so miserable.
So with all this said and the AC on all the time it gets so cold that you pop the hood and the pipes are literally white with frost. Not to mention it now snows in my car as well. (I'm not joking..) Driving while snow hits you in the face in the middle of summer can be a bit distracting let alone hard to explain if you get pulled over..
My mechanic is at a loss and can only recommend taking it to the dealer to have them figure it out. At this last time when he replaced the whole MPCU now my radio doesn't work. I've checked the fuses (under the hood/back of the radio & new control unit), wiring etc. Nothing is out of place. There are no other issues at this point, windows/automatic door locks/overhead lights all work.
I was curious if it could be as simple as the actual button on the dash that "Turns on the AC Unit" as for the radio I'm at a loss and will have to give in and take it somewhere else to have that looked at. Does anyone have any thoughts or maybe had similar situations that could offer some help?
07-21-2016
#2
If you think a good mechanic is expensive, try hiring a bad one
Re: 2002 Civic AC Mystery..
only way I can make the ac even work is to connect a ground wire to the frame
I was curious if it could be as simple as the actual button on the dash that "Turns on the AC Unit"
(That's the control panel with the dials, not the pushbutton switches.)
Easy check, pull it out and disconnect it, in connector/terminal A4 find the blue wire and ground it. Start the engine up. If the AC kicks on in the engine compartment, the panel is probably bad.
Radio could be anything from blown fuse in either fuse box or maybe a dash harness that wasn't fully seated into the new dash fuse box, or fuses not in the correct holes in the new fuse box. Stock radio or aftermarket? Pull it out and verify 2 powers and ground at the back of the unit?
