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Home >> Toyota >> 2012 >> Yaris SE, Automatic Trans >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Hatchback) (Diagnostics - Introduction) >> SFI SYSTEM (for Hatchback) >> Problem Symptoms Table >> Problem Symptoms Table
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Problem Symptoms Table

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SFI SYSTEM

Symptom Suspected Area See
Engine does not crank (Does not start) Battery Refer to ON-VEHICLE INSPECTION - Step 1
Starter relay Refer to ON-VEHICLE INSPECTION - Step 1
Starter (except Cold Area) Refer to INSPECTION
Starter (for Cold Area) Refer to INSPECTION
Clutch start switch assembly (for Manual Transaxle) Refer to INSPECTION - Step 1
Park/neutral position switch assembly (for Automatic Transaxle) Refer to INSPECTION
Starter signal circuit Refer to Starter Signal Circuit
No initial combustion (Does not start) ECM power source circuit Refer to ECM Power Source Circuit
Crankshaft position sensor Refer to INSPECTION PROCEDURE
Ignition system Refer to ON-VEHICLE INSPECTION - Step 1
Fuel pump control circuit Refer to Fuel Pump Control Circuit
Fuel pump Refer to INSPECTION
Fuel injector circuit Refer to Fuel Injector Circuit
Valve timing Refer to PROCEDURE - Step 5
VC output circuit (ECM 5 V output) Refer to VC Output Circuit
Camshaft position sensor Refer to INSPECTION PROCEDURE
Starter signal circuit Refer to Starter Signal Circuit
Engine immobilizer system (w/ Engine Immobilizer System) Refer to HOW TO PROCEED WITH TROUBLESHOOTING
ECM Refer to TERMINALS OF ECM 
Engine cranks normally but difficult to start Fuel pump control circuit Refer to Fuel Pump Control Circuit
Fuel pump Refer to INSPECTION
Fuel injector circuit Refer to Fuel Injector Circuit
ECM power source circuit Refer to ECM Power Source Circuit
Starter signal circuit Refer to Starter Signal Circuit
Engine coolant temperature sensor Refer to INSPECTION
Intake system Refer to ON-VEHICLE INSPECTION - Step 1
Ignition system Refer to ON-VEHICLE INSPECTION - Step 1
Spark plug Refer to ON-VEHICLE INSPECTION - Step 3
Throttle with motor body assembly Refer to INSPECTION
Compression Refer to ON-VEHICLE INSPECTION - Step 10
Incomplete intermittent combustion occurs (Does not start) Fuel pump control circuit Refer to Fuel Pump Control Circuit
Fuel pump Refer to INSPECTION
Fuel line Refer to ON-VEHICLE INSPECTION
Ignition circuit Refer to INSPECTION PROCEDURE
Ignition system Refer to ON-VEHICLE INSPECTION - Step 1
Fuel injector circuit Refer to Fuel Injector Circuit
ECM power source circuit Refer to ECM Power Source Circuit
Starter signal circuit Refer to Starter Signal Circuit
Crankshaft position sensor Refer to INSPECTION PROCEDURE
Camshaft position sensor Refer to INSPECTION PROCEDURE
Engine immobilizer system (w/ Engine Immobilizer System) Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Valve timing Refer to PROCEDURE - Step 5
High engine idle speed Throttle with motor body assembly Refer to INSPECTION
Intake system Refer to ON-VEHICLE INSPECTION - Step 1
A/C signal circuit Refer to HOW TO PROCEED WITH TROUBLESHOOTING
ECM power source circuit Refer to ECM Power Source Circuit
Engine coolant temperature sensor Refer to INSPECTION
PCV valve and hose Refer to COMPONENTS
Low engine idle speed (Poor idling) Throttle with motor body assembly Refer to INSPECTION
A/C signal circuit Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Fuel pump control circuit Refer to Fuel Pump Control Circuit
Fuel pump Refer to INSPECTION
Intake system Refer to ON-VEHICLE INSPECTION - Step 1
PCV valve and hose Refer to COMPONENTS
Rough idling Compression Refer to ON-VEHICLE INSPECTION - Step 10
Ignition system Refer to ON-VEHICLE INSPECTION - Step 1
Spark plug Refer to ON-VEHICLE INSPECTION - Step 3
Fuel injector circuit Refer to Fuel Injector Circuit
ECM power source circuit Refer to ECM Power Source Circuit
Fuel pump control circuit Refer to Fuel Pump Control Circuit
Fuel pump Refer to INSPECTION
Fuel line Refer to ON-VEHICLE INSPECTION
Throttle with motor body assembly Refer to INSPECTION
Intake system Refer to ON-VEHICLE INSPECTION - Step 1
Purge VSV Refer to INSPECTION
PCV valve and hose Refer to COMPONENTS
Air fuel ratio sensor Refer to INSPECTION PROCEDURE
Heated oxygen sensor Refer to INSPECTION PROCEDURE
Mass air flow meter Refer to ON-VEHICLE INSPECTION
Knock sensor Refer to INSPECTION
External part malfunction (Increase in load: A/C system, automatic transaxle system, etc.) -
Hunting (Poor idling) Throttle with motor body assembly Refer to INSPECTION
Intake system Refer to ON-VEHICLE INSPECTION - Step 1
PCV valve and hose Refer to COMPONENTS
Air fuel ratio sensor Refer to INSPECTION PROCEDURE
Mass air flow meter Refer to ON-VEHICLE INSPECTION
Hesitation/poor acceleration Fuel pump control circuit Refer to Fuel Pump Control Circuit
Fuel pump Refer to INSPECTION
Fuel line Refer to ON-VEHICLE INSPECTION
Spark plug Refer to ON-VEHICLE INSPECTION - Step 3
Ignition system Refer to ON-VEHICLE INSPECTION - Step 1
Fuel injector circuit Refer to Fuel Injector Circuit
ECM power source circuit Refer to ECM Power Source Circuit
Mass air flow meter Refer to ON-VEHICLE INSPECTION
Throttle with motor body assembly Refer to INSPECTION
Intake system Refer to ON-VEHICLE INSPECTION - Step 1
Valve timing Refer to PROCEDURE - Step 5
Compression Refer to ON-VEHICLE INSPECTION - Step 10
Brake override system Refer to Brake Override System
Surging (Poor driveability) Spark plug Refer to ON-VEHICLE INSPECTION - Step 3
Fuel pump control circuit Refer to Fuel Pump Control Circuit
Fuel pump Refer to INSPECTION
Ignition system Refer to ON-VEHICLE INSPECTION - Step 1
Fuel injector circuit Refer to Fuel Injector Circuit
ECM power source circuit Refer to ECM Power Source Circuit
Mass air flow meter Refer to ON-VEHICLE INSPECTION
Variable Valve Timing (VVT) system Refer to INSPECTION PROCEDURE
Compression Refer to ON-VEHICLE INSPECTION - Step 10
Engine stalls soon after starting Fuel pump control circuit Refer to Fuel Pump Control Circuit
Fuel pump Refer to INSPECTION
Spark plug Refer to ON-VEHICLE INSPECTION - Step 3
Ignition system Refer to ON-VEHICLE INSPECTION - Step 1
Fuel injector circuit Refer to Fuel Injector Circuit
ECM power source circuit Refer to ECM Power Source Circuit
Mass air flow meter Refer to ON-VEHICLE INSPECTION
Variable Valve Timing (VVT) system Refer to INSPECTION PROCEDURE
Throttle with motor body assembly Refer to INSPECTION
Intake system Refer to ON-VEHICLE INSPECTION - Step 1
PCV valve and hose Refer to COMPONENTS
Compression Refer to ON-VEHICLE INSPECTION - Step 10
Engine stalls only during A/C operation A/C signal circuit Refer to HOW TO PROCEED WITH TROUBLESHOOTING
ECM Refer to TERMINALS OF ECM 
Unable/difficult to refuel Fuel system (canister, fuel tank, etc.) -