Electronic Control Unit (Ecu)

1984 Toyota Cressida 4D WagonSECTION Electronic Control Unit (Ecu)

The ECU is mounted behind glove compartment under instrument panel. 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 data sensors and switches. These signals are processed by the ECU for controlling 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" lamp will also be lit when the computer malfunctions.

Fig 1: Electronic Control Unit Electrical Connector I.D.
G42141Courtesy of Β© TOYOTA, LICENSE AGREEMENT TMS1002
RENDER: 1.0x

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Stop DIY work and contact a certified mechanic immediately if any of the following apply:

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