To find the error, return to the Income section of your wife's return and review all entries from accuracy. Sometimes just entering information on the wrong box number will cause this. For example, if an entry for income tax deducted is placed in an income box, the income will be added and no tax will show as deducted.
It's important to note that if you've elected to split your pensions with your spouse, the income that has been split will be added to the spouse's income for tax purposes.
