LCD Display OBD TPMS Tire Pressure Monitor Car Tire Safe Alarm System. For Toyota Highlander 2008-2014 For Toyota Auris 2007-2012 For Toyota Sienna 2011-2014 For Toyota Corolla 2008-2013 For Toyota RAV4 2008-2012 Working principle: When the tires are underinflated , the tire radius become smaller , wheel speed become higher , when the tires are overinflated , tire radius become larger at the same time wheel speed become lower .The Car OBD get the original ABS data , once tire underinflated , it result to abnormal data , then monitor alarm . the screen show the value is not the actual tire pressure value bar, it an is analog value of the tire pressure. Notice: 1.the monitor screen show "2.4'mean tire pressure normal . 2.when the tire pressure leak up 20%-25%.it will show "1.8" and alarm. 3.when the tire pressure leak up 50% or more.it will show "1.0" and alarm. OBD TPMS advantages: 1. No need to disassembly device, easy to install. 2. No need to install sensors and replace battery. 3. Safety, it utilize original car ABS data to judge the tire status . can discover tire hidden danger in time. OBD TPMS disadvantages: display the value is not the actual tire pressure value . Size:2.3cm*3.4cm Package Including : * Displayer/Button *OBD plug Connector *Installation tool *User Manual