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Control Module: Description and Operation


PURPOSE

The TCU determines shift and converter lockup timing based on signals from the sensors. The valve body solenoids are activated/deactivated accordingly.

OPERATION

The TCU has a self diagnostic program. Component and circuitry malfunctions can be diagnosed with the DRB II tester. Once a malfunction is noted and stored in TCU memory, it is retained even after the problem has been corrected. To cancel a stored malfunction, simply disconnect and reconnect the "Trans." fuse in the TCU harness.