LEMON Manuals: Even more car manuals for everyone
Home >> Lexus >> 2020 >> UX 200 Luxury >> Repair and Diagnosis >> External Pages >> Different car >> Section 47 (Hybrid Control System (Diagnostic Codes) (3 Of 5)) >> Hybrid Control System >> DTC P1C77-79: Engine Failed to Start Mechanical Linkage Failure [10/2018 - ] >> Description

DTC P1C77-79: Engine Failed to Start Mechanical Linkage Failure [10/2018 - ]: Description

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2024 Lexus UX 250h, 2023 Lexus UX 250h, 2022 Lexus UX 250h, 2021 Lexus UX 250h, and 2020 Lexus UX 250h. However, it is still accessible from the selected car via links, so may be relevant.

The hybrid vehicle transaxle assembly consists of the planetary gear unit, generator (MG1) and motor (MG2). The planetary gear unit uses a planetary gear to split the engine output into mechanical power and electrical power in accordance with driving requests when the vehicle is being driven or the HV battery is being charged. When accelerating, motor (MG2) assists engine output by increasing vehicle driving force. Motor (MG2) also converts braking energy, which would otherwise be consumed in the form of heat during braking, into electrical energy. This recovered energy is stored in the HV battery. Generator (MG1) supplies power, which is used for charging the HV battery or driving motor (MG2), and also regulates the amount of electricity being generated. In addition, generator (MG1) is used as a starter motor to start the engine.

If the hybrid vehicle control ECU detects that the engine or transaxle gear has seized, the hybrid vehicle control ECU will perform fail-safe control. Also, if a substance or object is preventing the engine or transaxle internal components from rotating, the hybrid vehicle control ECU will perform fail-safe control.

Fig 1: Hybrid Vehicle Transaxle Assembly
GTY555691Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
DTC No. Detection Item DTC Detection Condition Trouble Area MIL Warning Indicate
P1C7779 Engine Failed to Start Mechanical Linkage Failure The engine does not start even though it is being cranked (transaxle input circuit malfunction (engine system))
(1 trip detection logic)
  • Hybrid vehicle transaxle assembly
  • Transmission input damper assembly
  • Engine
Does not come on Master Warning:
Comes on
RELATED DATA LIST

DTC No. Data List
P1C7779
  • Engine Speed
  • Generator Revolution
  • Motor Revolution
  • Target Generator Torque
  • Generator Torque