DTC P1644-9E: Starter Circuit Stuck On [12/2019 - 10/2022]: Description

The engine stop and start ECU detects abnormalities in the DI (+B) value that is input from the integrated IC (stop and start backup boost converter integrated IC) to the CPU.

If a logical inconsistency occurs between the +B value and DI (+B) value input to the CPU, the engine stop and start ECU stores DTC P1644-9E and blinks the stop and start cancel indicator.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Warning Indicate	Memory	Note
P1644-9E	Starter Circuit Stuck On	Both of the following conditions are met for 1 second or more (1 trip detection logic): +B terminal voltage is 9.16 V or more. Low battery voltage is detected.	Wire harness or connector Engine stop and start ECU	Blinks	DTC stored	SAE Code: P1644