Replacement TCMs donÂ’t come with trim data. After installation, you need to run a teach-in (hydraulic pressure characteristic calibration) procedure with the HDS. The problem is that A/T DTC P287C (transmission adaptive values not learned) is set, which prevents teach-in.
This happens because the TCM is programmed to look for trim data any time the ignition is cycled. If the TCM doesnÂ’t see that trim data, it sets A/T DTC P287C. If any DTCs are set, the TCM wonÂ’t initiate teach-in and, as a result, canÂ’t learn the trim data. ItÂ’s a classic catch-22 situation.
