Need help with v/a problem..tech no help.

[chevnut55]

My 69 is finished except for some program tuning, but have driven it 700 miles so far and Im having problems with my vintage air .
It never seemed enough to cool the car, I thought it was because it was a convertible so I just did not use it much.
now it got colder Im using the heat and the ac compressor is coming on with the heat. I think or hope it was due to me not shutting off the ac all the way before tuning it to heat..who knows because noew the compressor does not turn on.
It was also running the blower when the battery was disconnected , V/A says its because it was searching for a ground ..makes no sense that it would run until the battery was dead then the whole system have a fit but ok, guess leaving the heater hooked up all time will have to do.
Everything else works fine and did for 700 miles but now the compressor will not turn on unless I put a test light on the blue wire at the relay and it will click on.
I called the 1st tech and he told me the ecu might be bad and to take it apart and test the 2 black wires and call before sending it back.
So after a day of tearing my dash and ac apart the 2nd tech is saying is the guy who wired my ls1 harness fault because the fan comes on with the compressor with the ls1 ecm a/c call . So I was told to have him look at it.
I explained that the car was done and it was working and the harness guy was a tool and is in another state, so he just kept explaining how I was a dumass and its not their fault or problem and I need to have a wiring guy look at it.
Everything is done to directions , it is charged correct, it worked fine for 700 miles, the relays are good. There is something that is not turning on the compressor before the relay.
I can not figure it out because the wires go in to the fancy ecu and That's where my understanding ends.
Since I have no help or anyone to ask does anyone have any clue where to look next?
V/A tech is usually helpful and is right on during the install when the instructions were not clear but not this time.
I need to get it fixed asap or have my wife shove a test light in the relay whenever we need to cool down.

[chevnut55]

After another day of being on the phone with a decent tech guy at vintage, I know have the dash apart and is now not drivable car that was finished.
still no ac. I narrowed it to the blue trigger wire on the relay but still had to test every part anyway , so far everything checks out. I know it has to be the ecu but they do not seem to want it to be that.
wish I never bothered with the a/c.

[130fe]

Assuming you have a Gen IV, have you tried reprogramming the ECM? Every time you disconnect battery power you are supposed to do it. There is a single grey wire near the relays. Starting on page 8-

http://www.vintageair.com/INSTRUCTIONS/492050%20REV%20A%2003.17.10.pdf

[Z06vet]

Has the freon possibly become low? That will keep the compressor from coming on to protect the compressor. If it was working before, and there were no wiring changes made, you may want to put a gauge on it to make sure sytem is still fully charged. Over that 7 months it could have lost some freon due to slow leak, especially since you say it was not that cold. The system hold about 2 lbs. Over or under charging will cause problems you describe. When using the heat/defrost, its very common for the compressor to cycle so that it doesnt sit idle during colder months. I know in both my cars the compressor cycles with heat or defrost on. On the AC trigger wire, I have used that wire to turn the fan on when the AC is turned on. The tech at vintage air told me that is not the correct way to have the fan operate. It has worked flawlessly for me for years, but they want you to use a trinary switch for fan operation. I guess I will eventually change it, but I dont see this as being your problem. Scott

[chevnut55]

Yes, I re programed it a few times just in case. The psi is still there and it blows cold air when the trigger wire is jumped.
I tested the temp probe and the control switch.
I did the same with the pcm trigger wire and the no so good tec told my it was the problem so I removed it.
I will put a manual switch for the fan to cool it better in traffic when the ac is off.
I knew nothing about a/c and this is my 1st car with it but Im quickly becoming a expert.
Hope I get it fixed before my house sells ,I only installed it because Im moving to s. fl.

[chevnut55]

Everything works again thanks to Ryan at vintage air.
The tech wanted me to replace the switch (witch I did any) was not the problem.
It turns out after sending the ecu and switch back for testing the ecu had damage somehow that they think was caused by water, I checked for leaks or condensation and did not see any, they also think it could have been cause by the ls1's computer tied in but it was disconnected because it did nothing anyway.
I did have a fan relay trigger off the compressor ground ,it does not draw much amps but I removed it just incase and sealed the ecu in a plastic bag.
I could run the fan off the pressure switch but I do not want to drain the system so I will install a manual switch so it not only comes on with the ac but I can turn it on to cool it better in traffic as long as I remember to turn it on with the a/c it should be fine.
I do not understand why the system does not have a separate controller to turn on fans or work with ls motors to make it easier but after a week under the dash Im just glad to get it working.