TRID not only requires you to monitor the APR from the LE to the CD, but you must also make sure your disclosed APR is accurate when compared to the actual APR. This is nothing new; the comparison has been required since 1969.
The tolerance for the Total of Payments (TOP), which only appears in the CD, has also existed since 1969, but instead of the previous $0.00 tolerance you now have $100. The TOP is calculated by adding together the principal, interest, mortgage insurance, and loan costs.
You should monitor all applicable tolerances. I would assume that whatever loan origination software system is used by your bank will properly calculate the TOP. But we have seen cases where the system accurately calculates the number, but it is still wrong because of an entry error by the bank, for example, an item that should be included in the loan costs is not included in the loan costs.
Neither the law nor the regulation contains a cure for TOP violations, but presumably adjusting the TOP so the borrower does not pay more than disclosed would “cure” the violation.