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Electronic Control Unit

Electronic Control Unit (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.

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 warning light will also be on when the computer malfunctions.

Fig 1: 2S-E - Electronic Control Unit Electrical Connectors
G74112Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 2: 3S-GE - Electronic Control Unit Electrical Connectors
G74113Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002