DTC P1644-00: ECU Internal Error [12/2019 - 10/2022]: Description

If a malfunction is detected in the starter circuit, the engine stop and start ECU stores DTC P1644-00 and blinks the stop and start cancel indicator.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Warning Indicate	Memory	Note
P1644-00	ECU Internal Error	Both of the following conditions are met for 0.2 seconds or more (1 trip detection logic): Ignition switch ON. Malfunction in starter circuit (STA).	Wire harness or connector ST relay Engine stop and start ECU	Blinks	DTC stored	SAE Code: P1644