{"model":"mk4","model_name":"MK4 Supra","vehicle":"Toyota Supra A80 (1993–2002, 2JZ-GE / 2JZ-GTE)","document":"Repair Manual","section":"TGE","section_name":"Troubleshooting 2JZ-GE","page":58,"pages_in_section":105,"title":"Dtc 31 Volume Air Flow Meter Circuit","section_header":"Engine — 2JZ–GE Engine Troubleshooting","ocr_text":"EG–438\n\nENGINE – 2JZ–GE ENGINE TROUBLESHOOTING\n\nDTC 31 Volume Air Flow Meter Circuit\n\nCIRCUIT DESCRIPTION\n\nAs shown in the figure at right, when a pillar (Vortex generating body is placed in the path of a uniform flow, vortices called Karman–Vortex are generated downstream of the object. Using this principle, a vortex generator is placed inside the volume air flow meter. By measuring the frequency of the vortices generated, the ECM can determine the volume of air flowing through the volume air flow meter. The vortices are detected by their exerting pressure on thin metal foil mirror) surfaces and a light emitting element and light receptor (LED and photo transistor) positioned opposite the mirror which optically senses the vibrations in the mirror. The ECM uses these signals mainly for calculation of the basic injection volume and the basic ignition advance angle.\n\nKarman-Vortex\n\nLeaf Spring\nLuminous Diode\nMirror\nAir Flow\nKarman-Vortex\nVortex Generating Object\nPressure Directing Hole\nPhoto Transistor\n\nFI3045\n\nFI4504\n\nDTC No. | Diagnostic Trouble Code Detecting Condition | Trouble Area\n\n31\nAll conditions below are detected:\n(a) No volume air flow meter signal to ECM for 2 sec. when engine speed is above 300 rpm\n(b) Engine stall\n• Open or short in volume air flow meter circuit\n• Volume air flow meter\n• ECM\n\nif the ECM detects diagnostic trouble code \"31\", it operates the fail safe function, keeping the ignition timing and fuel injection volume constant and making it possible to drive the vehicle.\n\nWIRING DIAGRAM\n\nVolume Air Flow Meter\n\n4\nL-R\n41\nE9 VCC\n5 V\n\n5\nBR\n\n3\nLG-B\n66\nE9 KS\n5 V\n\nBR\n69\nE9 E1\n\nBR\nED\n\nEngine Control Module\n\nFI6880","image":"https://tsrm.sasquatchvc.com/images/mk4/TGE/TGE_058.png","url":"https://tsrm.sasquatchvc.com/mk4/tsrm/TGE/58","prev":{"page":57,"url":"https://tsrm.sasquatchvc.com/mk4/tsrm/TGE/57","api":"https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/57"},"next":{"page":59,"url":"https://tsrm.sasquatchvc.com/mk4/tsrm/TGE/59","api":"https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/59"},"section_url":"https://tsrm.sasquatchvc.com/mk4/tsrm/TGE","section_api_pages":["https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/1","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/2","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/3","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/4","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/5","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/6","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/7","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/8","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/9","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/10","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/11","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/12","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/13","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/14","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/15","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/16","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/17","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/18","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/19","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/20","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/21","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/22","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/23","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/24","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/25","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/26","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/27","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/28","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/29","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/30","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/31","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/32","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/33","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/34","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/35","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/36","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/37","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/38","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/39","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/40","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/41","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/42","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/43","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/44","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/45","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/46","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/47","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/48","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/49","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/50","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/51","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/52","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/53","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/54","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/55","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/56","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/57","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/58","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/59","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/60","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/61","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/62","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/63","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/64","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/65","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/66","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/67","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/68","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/69","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/70","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/71","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/72","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/73","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/74","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/75","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/76","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/77","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/78","https://tsrm.sasquatchvc.com/api/pages/mk4/tsrm/TGE/79","https://tsrm.sasqua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transcript of a scanned Toyota factory manual page; verify critical values (torque specs, part numbers) against the image."}