5 Fan Motor?

[leanderjanell]

Hi all, I have a 2005 Mazda 5, bought used in 2011. This summer, what I thought was the AC compressor started making a very odd noise when the motor would cycle down. Sounds like a deep growling in the cabin, light clicking outside. Doesn't sound like something in the fan, not like a card in bicycle spokes. Cycles every 20 seconds to a minute or two. When I was on the highway and the motor would cycle, the AC would blow warm for a minute. So I didn't run the AC all summer, not having cash to get a new compressor. Now I've found it does the same thing when I run any aspect of the fan - heat, defrost, you name it. The motor cycles and the same "growling" noise happens when it cycles down. Jiffy Lube ran a diagnostic for me and got:
Number of Detected ECU's: 2
Active Protocol: ISO 15765-4
ID: $7E8 Physical CAN ID
ID: $7E9 Physical CAN ID
which of course they had no idea what it meant. Had them listen to the sound since I was getting an oil change anyway, guy had never heard the sound before. Had to go to AutoZone a couple days later and get a new battery and AutoZone guy had never heard the sound before.
Any clues to what this might be would be greatly appreciated!

 

[Davebert]

It might be a bad AC clutch, it is a know problem part for the M5.

 

[leanderjanell]

Easy to replace? This sound happens when the AC isn't used whatsoever, would the clutch control all aspects of the fan?

 

[Davebert]

When I had the AC clutch problem the knocking sound was there most of the time even with the AC off. Because the noise was not constant if was difficult to find the problem, I had to bring it into the mechanic and left it there for them to find the problem. I did not do the work so I don't know how difficult it is to change.