It gives me great pleasure to announce that I have successfully repaired my Honda Civic's A/C problem!!!! And I did so without ever having to crack the sealed system open.
As I have stated previously, I found that my Compressor Thermal Protector (CTP) switch was stuck in an open state, which prevented the compressor clutch field coil from ever seen voltage, and therefore never engaging. It is the ONE glaringly obvious fault in the system that I can detect. By Occam's Razor, this would be both my easiest and best bet at a cure. I found a genuine Honda replacement part on http://hondapartscheap.com
for under $59.00 (down from the list price of $84.00). If you're working on Hondas this site will save you some major $$$. Highly recommended.
I will spare you the details of GETTING ACCESS to the compressor. I will simply say that I had to dislodge the power steering pump and reservoir (not opening that system, it can be pushed out of the way) and removing the alternator. Suffice to say that it was a cramped and knuckle-brutal task to get in there. I like Honda's style of belt tensioners used here on the PS pump and alternator, though the use of wing-nut heads instead of a hex-head bolt was a fail.
Here is what the compressor looks like with PS pump and alternator out of the way:
The device with two red wires entering it is the CTP switch. It was an M'Fer
to remove! I ended up grinding out the black plastic insulated interior with a Dremel on low-speed, using a snake extension. I went very slowly to only remove the soft plastic interior of the old CTP switch.
Once the plastic interior was removed I could then use a pick to remove the copper outer housing of the CTP switch. It is glued into the body of the compressor with silicone sealant. There is not much to it, but MAN is it a bear to clean out and remove!!!!
Next I cleaned the CTP switch cavity in the compressor with the Dremel and a grinding stone bit. The Dremel speed was on the slowest possible setting. I only wanted to clean out old silicone sealant and dirt.Time for Reassembly!
This is the new Honda CTP switch to be installed:
This marks the point in the job when the ratchets are switched from "lefty-loosey" to "righty-tighty". It's a very pleasing moment to say the least! Again, I will not bore you all with the process of reassembly, with the exception of two things. First: whenever I dig into a system that probably hasn't been touched since the factory, I ALWAYS clean all rust scale off my bolts and nuts, clean the threads, and reassemble with anti-seize compound as a just-in-case I ever have to do anything in this area again. It takes only a moment, and it also aids in the reassembly process. Second: the AC/Alternator and Power Steering belts are both over 14 years old and have 95k miles on them. They looked okay from the top, but they showed severe dry rot and cracking on the underside. They are cheap to replace, and since I'm in there anyway it is smart to do so now.
I reassembled the AC Compressor and Alternator first, then started the engine to test. System voltage at the battery was over 14v so the charging system is happy, and when I went into the cab to test the AC I was greeted by nice COLD air. AAAAAAAhhhhhhhhhhh!
I had purchased a new O-ring set, a new dryer, and new valve stems and caps, just in case I needed to evacuate and open the system. I didn't actually need them, though I did use the new valve caps to replace the old ones. Compared to the cost saved by NOT replacing the compressor (a bill of around $230 for a new Denso unit), the few dollars wasted on unused o-rings/dryer is negligible.
I will also state that when testing my system pressures, I'm still showing around 30-35/160psi
. These readings were done on a cool day (around 79°F) with low humidity and in an area that had been shaded from the sun all day. That still seems like a low high-side pressure to me, but I'll take it for now.
Thank you all for being a sounding board and listening to me think out loud. I mostly want to thank Tom G, for being the voice of reason and making me pause from running out and buying a new compressor. Also, thank you to cornbinder89 for his reality check. I appreciate all of this site's collected knowledge and hard work!