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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 P1788-04: Gear Shift Control Module "B" (Main CPU) System Internal Failure [10/2022 - ] >> Description

DTC P1788-04: Gear Shift Control Module "B" (Main CPU) System Internal Failure [10/2022 - ]: Description

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The shift actuator ECU has 2 microcomputers.

If the microcomputer (system 2) detects a malfunction of the microcomputer (system 1), a malfunction notification is produced.

DTC No. Detection Item DTC Detection Condition Trouble Area MIL Warning Indicate DTC Output from Priority Note
P1788-04 Gear Shift Control Module "B" (Main CPU) System Internal Failure When the battery voltage is a certain value or more, a malfunction of the microcomputer (system 1) is continuously detected for a certain amount of time or more.
(1 trip detection logic)
Shift control actuator assembly (shift actuator ECU) Does not come on Multi-information Display Error Message 
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Transmission A SAE: P1788