Toyota has officially announced a recall of certain 2006 and 2007 model year Highlander hybrid and Lexus RX 400h vehicles. The recall will affect 45,500 Highlander hybrids and 36,700 RX 400h’s. The issue stems from the Intelligent Power Module (IPM) located inside the hybrid system inverter that contains a control board with transistors.
Certain transistors on the control boards in the affected vehicles were inadequately soldered and could be damaged from heat caused by a large current flow during heavy driving.
If this were to occur, warning lights would come on and in most cases the vehicle would enter a fail-safe driving mode, resulting in reduced power and a shorter driving distance. In more serious cases, the power supply circuit fuse could blow when the transistor is damaged. The blown fuse would cause the hybrid system to stop and the vehicle would cost to a stop.
Owners with affected vehicles will be notified by first class main in mid-July 2011. An inspection will be made at a Toyota dealer, and if the vehicle is affected, the IPM will be replaced at no cost.