Inspect the belt for cracks or damage. If the belt is cracked or damaged, replace it.
Check that the position of the auto-tensioner indicator (A) is within the standard range (B) as shown. If it is out of the standard range, replace the drive belt.

Multiplex Integrated Control System Description
Body Controller Area Network (B-CAN) and Fast Controller
Area Network (F-CAN)
The body controller area network (B-CAN) and the fast controller area network
(F-CAN) share information between ...
Accented Letters
...
Transmission End Cover Air Check Valve Inspection and Replacement (A/T)
NOTE:
There are two types of the transmission end cover; the type A and the
type B; and both types are available.
The differences between the types A and B of the end covers are:
...