Hi,
To download Standard sap form 16 PDF based output required to configured ADS with help of BASIS team.
Please use the T-Code : PC00_M40_F16, But download you should configured Adobe Document Services (ADS).
ADS details in following link.
http://help.sap.com/saphelp_erp2005/helpdata/en/43/27098edb036025e10000000a422035/content.htm
Following Check Points.
Payroll Area
Ccode
Fiscal year
Output format : click on Standar Layout and clikc on Execute the Standard form
Other way use form 16 SAP script base layout generate spool request without print immediate option.
Use spool to PDF convert standard program i.e. RSTXPDFT4.
Regards,
Venkat Polisetty