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Transmission Control Unit

The TCU's memory is programmed to provide the correct shift pattern for each gear selector range and driving mode. The TCU has a built-in self-diagnostic system, which allows the technician to find electrical system problems, even those which are intermittent. Electrical system failures are stored in the long-term memory. This memory stores up to 3 faults, which can be accessed through the use of Diagnostic Readout Box (DRB-II). After repairing an electrical system problem, the memory must be cleared. To clear the memory, disconnect the TCU connector for a period of at least 10 seconds.