DTC P1604-00: Startability Malfunction [06/2018 - 08/2021]: Description

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This DTC is stored when the engine does not start even though the STA signal is input or when the engine takes a long time to start, and when the engine speed is low or the engine stalls just after the engine starts.

Using the Techstream, the conditions present when the DTC was stored can be confirmed by referring to the freeze frame data. Freeze frame data records engine conditions when a malfunction occurs. This information can be useful when troubleshooting.

It is necessary to check if the vehicle ran out of fuel before performing troubleshooting, as this DTC is also stored when there is engine starting trouble due to running out of fuel.

DTC No.	Detection Item	DTC Detection Condition	MIL	Memory	Note
P1604-00	Startability Malfunction	Either conditions is met (1 trip detection logic): The engine speed is below 500 rpm with the STA signal on for a certain amount of time (refer to the illustration below). After the engine starts (engine speed is 500 rpm or more), the engine speed drops to 200 rpm or less within approximately 2 seconds.	Does not come on	DTC stored	SAE Code: P1604

Trouble Area
Ignition system	Spark plug Ignition coil assembly
Fuel system	Direct fuel injector assembly Port fuel injector assembly Fuel pump assembly (for high pressure side) Fuel pump (for low pressure side) Fuel pump control circuit Fuel suction plate sub-assembly Fuel main valve assembly Fuel line Purge VSV system Fuel quality (existence of foreign matter, degradation)
Intake and exhaust systems	Mass air flow meter sub-assembly Intake system (Air leaks or deposit accumulation) Throttle body with motor assembly Air fuel ratio sensor Heated oxygen sensor Cam timing oil control solenoid assembly Camshaft timing oil control valve assembly Variable Valve Timing system (VVT system)
Other control systems	ECM Wire harness or connector Knock control sensor Engine coolant temperature sensor
Engine	Water inlet with thermostat sub-assembly Engine assembly
High load from another system	Air conditioning system Power steering system Electrical load signal system A/T system