DTC P1604: Startability Malfunction: Description

WARNING: This page is about a different variant/trim than selected.

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.	DTC Detection Condition	Trouble Area
P1604	Either condition is met: The engine speed is below 500 RPM with the STA signal on for a certain amount of time (refer to the illustration below) (1 trip detection logic). After the engine starts (engine speed is 500 RPM or more), the engine speed drops to 200 RPM or less within approximately 2 seconds (1 trip detection logic).	Immobiliser system Engine assembly (excess friction, compression loss) Starter assembly Crankshaft position sensor Camshaft position sensor Engine coolant temperature sensor Fuel pump Fuel pump control system Fuel pipes Fuel injector Throttle body Fuel pressure regulator Battery Drive plate Spark plug Ignition coil circuit Intake system Camshaft timing oil control valve assembly Mass air flow meter Air fuel ratio sensor Valve timing Fuel Purge VSV Intake valve Exhaust valve ECM

Fig 1: Engine Coolant Temperature Chart

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Reference waveforms showing a normal cold engine start

Fig 2: Identifying Waveform 1
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Reference waveforms showing a normal warm engine start

Fig 3: Identifying Waveform 2
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Reference waveforms showing an engine stop after normal idling

Fig 4: Identifying Waveform 3
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Reference values when there is an air leak in the intake system during starting difficulty

FREEZE FRAME DATA P1604 STARTABILITY MALFUNCTION

Parameter	-3	-2	-1	0	1	Unit
Engine Speed	398	325	221	159	114	RPM
Calculate Load	43.1	42.7	43.1	87.4	87.4	%
Vehicle Load	28.2	26.2	26.6	17.2	15.0	%
MAF	3.01	2.28	1.59	0.75	0.48	gm/sec
Atmosphere Pressure	14.5	14.5	14.5	14.5	14.5	psi (gauge)
Coolant Temp	185	185	185	185	185	F
Intake Air	115	115	115	115	115	F
Battery Voltage	12.460	12.382	12.324	12.324	12.343	V
Throttle Sensor Volt %	16.4	16.0	17.6	16.0	16.0	%
Throttle Sensor #2 Volt %	48.6	47.8	49.8	47.8	47.8	%
Throttle Sensor Position	0.0	0.0	0.0	0.0	0.0	%
Throttle Motor DUTY	17.6	16.0	16.0	16.0	16.0	%
Injector (Port)	4240	4302	4612	4612	7776	μs
Injection Volume (Cylinder 1)	0.274	0.274	0.187	0.187	0.187	ml
Fuel Pump/Speed Status	ON	ON	ON	ON	ON
EVAP (Purge) VSV	0.0	0.0	0.0	0.0	0.0	%
Evap Purge Flow	0.0	0.0	0.0	0.0	0.0	%
Purge Density Learn Value	0.000	0.000	0.000	0.000	0.000
EVAP Purge VSV	OFF	OFF	OFF	OFF	OFF
Target Air-Fuel Ratio	0.864	0.873	0.882	0.883	0.830
AF Lambda B1S1	0.999	0.999	1.001	1.002	1.005
AFS Voltage B1S1	3.298	3.298	3.307	3.312	3.327	V
O2S B1 S2	0.015	0.015	0.015	0.015	0.015	V
Short FT #1	0.000	0.000	0.000	0.000	0.000	%
Long FT #1	3.906	3.906	3.906	3.906	3.906	%
Total FT #1	0.000	0.000	0.000	0.000	0.000
Fuel System Status #1	OL	OL	OL	OL	OL
IGN Advance	8.0	7.0	6.0	0.0	0.0	deg
Knock Feedback Value	-3.0	-3.0	-3.0	-3.0	-3.0	CA
Knock Correct Learn Value	19.0	19.0	19.0	19.0	19.0	CA
VVT Control Status #1	OFF	OFF	OFF	OFF	OFF
Starter Signal	Close	Close	Close	Close	Close