bypass paper size change? fp7718

[lowrider]

how do you change the paper size of the sheet bypass? i have a 7718 that has the papersize of the sheet bypass stuck on letter, it half scans if i use a3, theres f5 14, 15, 16 selection for all paper trays but none for the sheet bypass? how do you change this? (the 7718 has no paper sensor on the bypass so this is not the problem)... can anyone help me with this? thanks

[yakyitz]

there are three paper size sensors on the bypass, when you move the paper guides there are switches inside the tray and one flag sensor on the extension of the bypass tray (for lgl or ldr paper)

[lowrider]

thanks yakyitz, in the 7735 models the paper sensors are there, but on the 7718 there are no sensors on the bypass tray, after hours of looking on the function mode to change the paper size i realized that it can be changed just using the user mode, however this is not true to all 7718, i specifically have two units that cant be changed at all, any other ideas on how to change this? thanks