Air Conditioning problem
1996 Acura Integra 4 cyl Front Wheel Drive Manual 150000 miles
AC stops blowing cold when driving over 45-50mph. When Im ideling its blows cold gets down to 47 degrees. Even if im doing 60mph and throw in Nutral its starts to blow cold as soon as I put in 5th gear and engage the clutch it stops blowing cold in a minute or so. I know that my compressor clutch is good. How? I ran an + power line straight from battery. And went for a ride and my ac worked at all times no matter how fast or slow I was going.
I have checked for any leaks.
I had a shop do vacuume and re-charge my ac. They also checked the low and high pressure and replaced pressure valve. No leaks were found. I checked for any bad fuses or relays none were found.
The AC clutch relay is activated by a ground circuit in the Engine Control Module and you might have a fault with the ECM for this circuit causing the compressor to cut off at high speeds.
The ground circuit is at ECM connector A terminal # 17. ECMs are known to fial for this circuit intermittently.
May, 12, 2010 AT 9:16 PM
I have all aready replaced my ECU once about 2 days ago and was getting the same problem. Now what I have figured out after long day of work is that when I disconect my speed sensor my AC seems to work fine at any speed. But as soon as I connect it it does same problem. Now I dont know if it will fix anything even if I buy a new Speed Sensor cause logically I cannnot imagine how that is tied with my AC problem?
May, 16, 2010 AT 8:02 AM
Sorry for the delay in replying. Had some trouble with connections and could not log in or had very slow connections for past few days.
You are correct. I could not link the VSS to the AC operations and there are no direct relationship between them. The only thing in common would be the ground circuit connection.
Try checking/testing the PCM and VSS ground circuit, located on thermostat housing.
May, 17, 2010 AT 2:58 PM
Ok I will try that out thanks. This is very helpfull I can at least do something about my problem, to were I didnt even know were to start. I'll keep you posted thanks.
May, 25, 2012 AT 12:09 AM
I have the same problem. What are the PCM and VSS ground circuits and how do I check them?