Toner sensor error': a common problem with OKI printers — how to fix it? - Webcartridge
Led Head Cannot Be Recognized. (Error Code 131, 132, 133, 134); Service Call 131 To 134 (Led Head Missing); Toner Cartridge Cannot Be Recognized. ( Error Code 540, 541, 542, 543); Error Caused
How To Fix Errors with Oki Toner Cartridges - YouTube
How to solve Toner Sensor Error on Oki printers
OKI | How do I find and resolve Toner Sensor Errors?