I have a 2004 Mustang 3.9l. A/c clutch that's not engaging. I've tested both pressure switches and they are both fine. I hot-wired the a/c compressor and the clutch kicks in. I tested the voltage at the plug for the compressor, with it unplugged I have 12 volts at the wire. With it plugged in I only have around 4-5 volts. Could it be the CCRM? Thanks in advance for all the help.