M20A-FKS (ENGINE CONTROL): SFI SYSTEM: PROBLEM SYMPTOMS TABLE; 2023 - 2025 MY Corolla Corolla Hatchback [03/2023

PROBLEM SYMPTOMS TABLE

HINT:

Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.
Inspect the fuses and relays related to this system before inspecting the suspected areas below.

SFI System

Symptom

Suspected Area

Link

Engine does not crank (Does not start)

Flow chart [Engine difficult to start]

(Vehicle Control History Code: X0810, X0811 and/or X0812)

Battery

ST relay

Starter assembly

Starter signal circuit

Smart key system (for start function) (w/ Smart Key System)

VC output circuit (ECM 5 V output)

Park/Neutral position switch assembly (for K120)

Shift lever position sensor (for K121)

No initial combustion (Does not start)

Immobiliser system (w/ Smart Key System)

Immobiliser system (w/o Smart Key System)

ECM power source circuit

VC output circuit (ECM 5 V output)

Flow chart [Engine difficult to start]

(Vehicle Control History Code: X0810, X0811 and/or X0812)

Ignition system

Fuel system

Port fuel injector assembly

Direct fuel injector assembly

Crankshaft position sensor

Intake system

Valve timing

EGR valve assembly

No. 1 valve rocker arm sub-assembly*5

Engine cranks normally but difficult to start

ECM power source circuit

Flow chart [Engine difficult to start]

(Vehicle Control History Code: X0810, X0811 and/or X0812)

Throttle body with motor assembly

Fuel pump assembly (for high pressure side)

Fuel pump (for low pressure side)*1

Fuel pump (for low pressure side)*2

Fuel pump (for low pressure side)*3

Fuel pump (for low pressure side)*4

Engine coolant temperature sensor

Fuel system

Ignition system

Spark plug

Compression

Port fuel injector assembly

Direct fuel injector assembly

Crankshaft position sensor

Intake system

Valve timing

EGR valve assembly

No. 1 valve rocker arm sub-assembly*5

Incomplete intermittent combustion occurs (Does not start)

Flow chart [Engine difficult to start]

(Vehicle Control History Code: X0810, X0811 and/or X0812)

Fuel system

Ignition system

Port fuel injector assembly

Direct fuel injector assembly

Crankshaft position sensor

Intake system

Valve timing

High engine speed

Throttle body with motor assembly

ECM power source circuit

PCV system

Low engine speed (Poor idle)

Flow chart [Rough idling]

(Vehicle Control History Code: X0821, X0822, X0823, X0824, X082A, X082D and/or X082E)

Fuel system

Throttle body with motor assembly

Port fuel injector assembly

Direct fuel injector assembly

Fuel pump assembly (for high pressure side)

PCV system

Intake system

Rough idle

Flow chart [Rough idling]

(Vehicle Control History Code: X0821, X0822, X0823, X0824, X082A, X082D and/or X082E)

Throttle body with motor assembly

Port fuel injector assembly

Direct fuel injector assembly

Fuel pump assembly (for high pressure side)

Ignition system

Air fuel ratio sensor (sensor 1)

Air fuel ratio sensor (sensor 2)

Mass air flow meter sub-assembly

Manifold absolute pressure sensor

Compression

Fuel system

Spark plug

Intake system

Valve timing

EGR valve assembly

No. 1 valve rocker arm sub-assembly*5

Hunting (Poor idle)

Throttle body with motor assembly

ECM power source circuit

Flow chart [Rough idling]

(Vehicle Control History Code: X0821, X0822, X0823, X0824, X082A, X082D and/or X082E)

Fuel system

Spark plug

Intake system

Drive start control

Hesitation/Poor acceleration (Poor driveability)

Flow chart [Rough idling]

(Vehicle Control History Code: X0821, X0822, X0823, X0824, X082A, X082D and/or X082E)

Port fuel injector assembly

Direct fuel injector assembly

Fuel system

Fuel pump assembly (for high pressure side)

Ignition system

Spark plug

Intake system

Valve timing

No. 1 valve rocker arm sub-assembly*5

Brake override system

Drive start control

Lack of power

Flow chart [Lack of power]

(Vehicle Control History Code: X0844 and/or X0845)

Surging (Poor driveability)

Flow chart [Rough idling]

(Vehicle Control History Code: X0821, X0822, X0823, X0824, X082A, X082D and/or X082E)

Fuel system

Spark plug

Port fuel injector assembly

Direct fuel injector assembly

No. 1 valve rocker arm sub-assembly*5

Engine stalls soon after starting

Flow chart [Engine stalls]

(Vehicle Control History Code: X0800 and/or X0803)

Fuel system

Throttle body with motor assembly

Crankshaft position sensor

Ignition system

Fuel pump assembly (for high pressure side)

Intake system

Valve timing

EGR valve assembly

Engine stalls soon after slow down

Flow chart [Engine stalls]

(Vehicle Control History Code: X0800 and/or X0803)

Port fuel injector assembly

Direct fuel injector assembly

Throttle body with motor assembly

ECM

Crankshaft position sensor

Ignition system

MIL (Malfunction Indicator Lamp) malfunction

MIL Circuit

Meter/Gauge system (for 12.3 Inch Display)

Meter/Gauge system (except 12.3 Inch Display)

Unable/difficult to refuel

Fuel system (canister, refueling valve, roll over valve, fuel tank, etc.)

*1: w/o Canister Pump Module (for Double Wishbone Type Suspension)
*2: w/ Canister Pump Module (for Double Wishbone Type Suspension)
*3: w/o Canister Pump Module (for Torsion Beam Type Suspension)
*4: w/ Canister Pump Module (for Torsion Beam Type Suspension)

HINT:

*5: Check "Fuel Cut Elapsed Time" in the Data List. If the elapsed time is over 0 sec, then the engine speed is high (the engine speed at which fuel cut occurs + 500 rpm or more). In this situation, there is a possibility that a No. 1 valve rocker arm sub-assembly will become loose and malfunction, check that the No. 1 valve rocker arm sub-assemblies are properly installed.

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2023 - 2025 MY Corolla Corolla Hatchback [03/2023 - ]; M20A-FKS (ENGINE MECHANICAL): ENGINE UNIT: COMPONENTS