Backup camera failure is the #1 NHTSA complaint for 4th-gen RAV4. Water intrusion causes fogging inside the lens, progressive image degradation, or complete failure. Most common on 2013–2015, less frequent on 2016+, but worth checking on any example.
Shift to Reverse and evaluate the backup camera image. Look for fogging, condensation inside the lens, washed-out color, flickering, or black screen. Test in changing temperature if possible — fogging often appears after cool overnight sits.
Est. cost: $200–$450 camera replacement
Source: NHTSA complaint data — top complaint category for 4th gen