On the vehicles affected--roughly 177,000 of them--a filter between the two chambers of the reservoir can become clogged with sediment or rust residue, inhibiting fluid flow, and causing the brake-fluid level in one chamber to become too low.
When this happens, a warning light on the dashboard will illuminate. If the filter remains clogged long enough.
Low fluid level in one of the two reservoir chambers could lead to failure of the brakes' power assist, making it harder to stop the car.
Toyota says no accidents or injuries have resulted so far, so it's classifying the fix as a service campaign, not a full recall.
However, Consumer Reports is calling for a recall of these Camry Hybrid models, because the issue is acknowledged to be a defect in one of the car's critical safety systems.
Toyota dealers will replace the brake-fluid reservoirs on affected cars free of charge. Owners who have had this repair done previously can be reimbursed by getting an application from their dealer and supplying Toyota with documentation of the repairs.
Both the service campaign and the period for reimbursement run through June 30, 2017. After that date, owners will have to pay for the repairs themselves.
Camry Hybrid owners can contact their local Toyota dealers, who will see if a given car is affected by looking up its VIN. Queries can also be directed to Toyota Customer Service at 800-331-4331.