401(a)

I am new to payroll, and I have a W-2 issue.  We have a CalPERS PEPRA retirement plan 401(a). Last year, one of my employee tax persons stated that 401 (a) should be deducted from the wages on the W-2 and in box 12.  According to IRS and another tax person I contacted for this year W-2's,  the 401 (a) should be in Box 14 on the W-2 and is not deducted from wages.  I have the 401 (a) in our payroll item list under deductions as NONE (as QB does not have 401 (a) listed), and when I issued my W-2's for employees this year, the 401 (a) contributions did not show up in any box on the W-2. What is correct?