One problem related to brake antilock wheel speed sensor has been reported for the 2008 Toyota Highlander Hybrid. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2008 Toyota Highlander Hybrid based on all problems reported for the 2008 Highlander Hybrid.
I was driving straight on a city street at 40 mph when the vehicle stability control and check brake system warnings alerted, as well as the cabin alarm. At that time I pulled into a gas station and realized the brakes had gone soft and were not functioning properly. I turned off and restarted the car; the problem persisted. I cautiously drove a half mile to my house and connected my vehicle to a diagnostic tool. The codes indicated c1252-7 (brake booster pump motor), c1256-7 (low pressure accumulator), and c1345-7 (linear solenoid valve offset learning undone). The combination of codes points to the brake actuator and pump needing to be replaced. The brake pads, speed sensors, wheel bearings, and relays are all good. After much online research I discovered that brake actuator/pump failure is a common complaint on this vehicle and costs thousands to repair. 2006-2007 brake actuators are already recalled, as well as 07-11 camry hybrid and prius which use the same platform. I contacted a local Toyota dealership who offered no help. The part itself is $1800+ without factoring in labor. I am also troubled by the safety factor this malfunction presents, especially we're it to occur at a higher speed.