I purchased in a 90 corvette in top condition. The AC was still on R12 but looks new. Anyhow I went to convert it earlier to R34 but the clutch and compressor would not go on. Mechanic temporarily jumped clutch from battery to try and see if would turn and it did. Assures plenty of R34 in the system. Disconnected battery a minute several times, to no avail. There is no error code in the diagnostiv displays. The fuse is good. Is there another reset somewhere in the system? HELP!