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Home >> Toyota >> 2004 >> Matrix Base, FWD, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 130 (Engine Control System Self Diagnostics) >> Diagnostic Tests >> DTC P1646: Transmission Control Ecu Malfunction >> Diagnosis & Repair
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Diagnosis & Repair

WARNING: This page is about a different car, the 2003 Toyota MR2. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Using Toyota hand-held tester or scan tool, read FREEZE FRAME data. Freeze frame data records engine conditions when malfunction is detected.

For circuit wiring diagram, diagnosis and repair procedure, see Fig 1.

For identification of TCU harness connector terminals, see Fig 2.

For ECM location, see Figure. For ECM connector terminal view, see Figure.

For testing of systems or components, see SYSTEM & COMPONENT TESTING - 4-CYLINDER article. For removal and installation of components, see REMOVAL & INSTALLATION - 4-CYLINDER article.

Fig 1: DTC P1646 Diagnostic Procedure
G00249447Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 2: Identifying Transmission Control Electronic Control Unit Harness Connector Terminals
G00027303Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002