Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Problem Symptoms Table
When the malfunction is not confirmed in the diagnostic trouble code check and the problem still cannot be confirmed in the basic inspection, use this table and troubleshoot according to the priority order given below.
SFI SYSTEM
| Symptom | Suspected Area | See |
|---|---|---|
| Engine does not crank (Does not start) | 1. Immobilizer system | SYSTEM DESCRIPTION |
| 2. Generator | - | |
| 3. Hybrid system | HOW TO PROCEED WITH TROUBLESHOOTING | |
| 4. Park/neutral position switch | - | |
| No initial combustion (Does not start) | 1. ECM (Included in HV Control ECU) power source circuit | ECM POWER SOURCE CIRCUIT |
| 2. Fuel pump control circuit | FUEL PUMP CONTROL CIRCUIT | |
| 3. ECM (Included in HV Control ECU) | - | |
| Engine cranks normally but difficult to start | 1. Fuel pump control circuit | FUEL PUMP CONTROL CIRCUIT |
| 2. Compression | ON-VEHICLE INSPECTION | |
| Difficult to start with cold engine | 1. Ignition system | DTC P0351 IGNITION COIL "A" PRIMARY / SECONDARY CIRCUIT |
| 2. Spark plug | INSPECTION | |
| 3. Fuel pump control circuit | FUEL PUMP CONTROL CIRCUIT | |
| 5. Injector | DTC P0300 RANDOM / MULTIPLE CYLINDER MISFIRE DETECTED | |
| Difficult to start with warm engine | 1. Injector | DTC P0300 RANDOM / MULTIPLE CYLINDER MISFIRE DETECTED |
| 2. Ignition system | DTC P0351 IGNITION COIL "A" PRIMARY / SECONDARY CIRCUIT | |
| 3. Spark plug | INSPECTION | |
| 4. Fuel pump control circuit | FUEL PUMP CONTROL CIRCUIT | |
| High engine idle speed (Poor idling) | 1. ECM (Included in HV Control ECU) power source circuit | - |
| 2. A/C signal circuit (compressor circuit) | - | |
| 3. Electronic throttle control system | ON-VEHICLE INSPECTION | |
| 4. Air induction system | - | |
| 5. PCV hose | - | |
| Low engine idle speed (Poor idling) | 1. A/C signal circuit (compressor circuit) | - |
| 2. Fuel pump control circuit | FUEL PUMP CONTROL CIRCUIT | |
| 3. Electronic throttle control system | ON-VEHICLE INSPECTION | |
| 4. Air induction system | - | |
| 5. PCV hose | - | |
| Rough idling (Poor idling) | 1. Compression | ON-VEHICLE INSPECTION |
| 2. Fuel pump control circuit | FUEL PUMP CONTROL CIRCUIT | |
| 3. Electronic throttle control system | ON-VEHICLE INSPECTION | |
| 4. Air induction system | - | |
| 5. PCV hose | - | |
| Hunting (Poor idling) | 1. ECM (Included in HV Control ECU) power source circuit | - |
| 2. Fuel pump control circuit | FUEL PUMP CONTROL CIRCUIT | |
| 3. Spark plug | INSPECTION | |
| 4. Ignition system | DTC P0351 IGNITION COIL "A" PRIMARY / SECONDARY CIRCUIT | |
| 5. Injector | DTC P0300 RANDOM / MULTIPLE CYLINDER MISFIRE DETECTED | |
| 6. Electronic throttle control system | ON-VEHICLE INSPECTION | |
| 7. Air induction system | - | |
| 8. PCV hose | - | |
| Hesitation/Poor acceleration (Poor driveability) | 1. Fuel pump control circuit | FUEL PUMP CONTROL CIRCUIT |
| 2. Spark plug | INSPECTION | |
| 3. Ignition system | DTC P0351 IGNITION COIL "A" PRIMARY / SECONDARY CIRCUIT | |
| 4. Injector | DTC P0300 RANDOM / MULTIPLE CYLINDER MISFIRE DETECTED | |
| Surging (Poor driveability) | 1. Spark plug | INSPECTION |
| 2. Fuel pump control circuit | FUEL PUMP CONTROL CIRCUIT | |
| 3. Ignition system | DTC P0351 IGNITION COIL "A" PRIMARY / SECONDARY CIRCUIT | |
| 4. Injector | DTC P0300 RANDOM / MULTIPLE CYLINDER MISFIRE DETECTED | |
| Engine stalls soon after starting | 1. Fuel pump control circuit | FUEL PUMP CONTROL CIRCUIT |
| 2. Spark plug | INSPECTION | |
| 3. Ignition system | DTC P0351 IGNITION COIL "A" PRIMARY / SECONDARY CIRCUIT | |
| 4. Injector | DTC P0300 RANDOM / MULTIPLE CYLINDER MISFIRE DETECTED | |
| Engine stalls during A/C operation | 1. A/C signal circuit (Compressor circuit) | - |
| 2. ECM (Included in HV Control ECU) | - | |
| Unable/difficult to refuel | Refueling valve (canister) | - |
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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