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Home >> Lexus >> 2024 >> RX 500h >> Repair and Diagnosis >> External Pages >> Different car >> Section 12 (Electronic A/T Shift Lever System - Diagnostic Codes (2 Of 2) & Circuit Tests) >> Electronic Shift Lever System >> DTC P178A-14: Gear Shift Control Module "B" Wake-up Circuit Short to Ground or Open; DTC P178D-14: Gear Shift Control Module "B" (Sub CPU) Wake-up Circuit Short to Ground or Open [10/2022 - ] >> Description

DTC P178A-14: Gear Shift Control Module "B" Wake-up Circuit Short to Ground or Open; DTC P178D-14: Gear Shift Control Module "B" (Sub CPU) Wake-up Circuit Short to Ground or Open [10/2022 - ]: Description

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The shift actuator ECU starts when it receives a WAKE signal from the shift control ECU.

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Warning Indicate DTC Output from Priority Note
P178A-14 Gear Shift Control Module "B" Wake-up Circuit Short to Ground or Open When the battery voltage and BAT1 terminal voltage are a certain value or more, a low voltage is detected at the WAKE terminal
(1 trip detection logic)
  • Shift control actuator assembly (shift actuator ECU)
  • Transmission floor shift assembly (shift control ECU)
  • Harness and connector
Does not come on Multi-information Display Error Message 
  • Displayed
Transmission A SAE: P178B
P178D-14 Gear Shift Control Module "B" (Sub CPU) Wake-up Circuit Short to Ground or Open When the battery voltage and BAT1 terminal voltage are a certain value or more, a low voltage is detected at the WAKE terminal
(1 trip detection logic)
  • Shift control actuator assembly (shift actuator ECU)
  • Transmission floor shift assembly (shift control ECU)
  • Harness and connector
Does not come on Multi-information Display Error Message 
  • Displayed
Transmission A SAE: P178E