Okay, so I did a search and found out that chances are good that one of the relays on the ccu is probably going bad or I just need to do some cleaning back there, but what has me concerned is that even with the ccu turned off I'm still getting a couple of clicks when I turn the key to the number 2 and 3 position. Is there a relay buried back there that is also part of the ignition system?


As for trouble shooting the CCU; the aux pump has been disconnected for a year so I know it's not fried. My blower motor started going out once in a while a couple of months ago, so I replaced it with one from the junkyard which may also be on it's way out. Today when I got the cracking noise, I couldn't get the blower to come on with the defrost setting, but the AC compressor kicked in. On the other settings I was getting moderate air flow from the vents with no AC. I shut the HVAC system down for a few minutes, then turned on the AC and whola had good cold AC for an hour. Could worn brushes in the blower cause problems elsewhere? Thanks

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'81 300SD