Chirping / Squeaking from AHC on 04 LX470

[JETTIX2]

New to me 04 LX470 with 169k on it. All service records, had a rear AHC sensor at 135k. Otherwise, appears to be original AHC components.

When I start the truck cold (it's between 0F and 35F right now), I hear a chirping/squeaking from the rear for about 60 seconds, then it goes away........sounds almost like a squeaky fanbelt, but it's clearly from the rear of the truck. After 60 seconds or so, it dissapears. Almost like the AHC system "pumping" up one of the rear corners. I don't know enough about the system to know what's back there, and what might be making the noise. Seems to ride and drive fine.

Any thoughts?? Just making sure nothing is imminently ready to fail

 

[Flipped Bezel]

Do you see or feel the system adjusting truck level at the same time of the squeaking sound?

 

[JETTIX2]

Do you see or feel the system adjusting truck level at the same time of the squeaking sound?

I can't really detect any height change, but it only does it after it's been sitting for several hours, ie if I start it after an hour, it only squeaks for a couple seconds. I'm assuming it's just re-charging one of the rear accumulators or something.

 

[SurfSwitch]

Rear fan motor for AC/Heat maybe?

 

[JETTIX2]

Rear fan motor for AC/Heat maybe?

Hmm could be, I'll switch it off and check!