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Electronic Control Unit (Ecu)

The ECU controls all functions of the TCCS. The ECU consists of a printed circuit board enclosed within a metal box. The ECU receives signals from the data sensors and switches. These signals are processed by the ECU for controlling the EFI, ESA, ISC, EGR and ECT systems.

The TCCS has a fail-safe feature designed into the ECU. If the ECU malfunctions, a back-up circuit is activated to assist in getting the vehicle to a service facility. During this mode of operation, driveability will be minimal. The "CHECK ENGINE" light will also be lit when the computer malfunctions.

Fig 1: TCCS Component Locations
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