## Typical Automotive DTCs

### P0420 Emissions Control Malfunction

– Frequent Reasons:

Exhaust leaks [1]

– Suggested Repairs:

Replace catalytic converter https://carautorepair.site/

### P0171 Air-Fuel Ratio Error

– Likely Problems:

Fuel delivery problems

– Testing Procedure:

Inspect injectors [1][7]

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## Car Maintenance Terms

### Electronic Braking System

– Function: Prevents wheel lockup [7]

### ECM/ECU (Engine Control Module)

– Responsibility: Manages fuel injection [7]

### Drivetrain Components

– Includes: Differential [7]

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## Repair Process Steps

1. **Symptom Assessment**:

Conduct road test

2. **Part Evaluation**:

Measure resistance

3. **Defective Unit Swap**:

Follow torque specs

4. **Final Quality Check**:

Confirm warning light reset

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## Essential Tools

| **Tool Type** | **Examples** | **Purpose** |

|—|—|—|

| OBD-II Tool | Innova | Live data streaming |

| Mechanical Tools | Smoke machine | Electrical testing |

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## Repair Documentation Sources

### Vehicle Service Database

– Capabilities:

Component locations [8]

Factory repair procedures

### Digital Assistants

– Auto Repair Documents:

Component testing guides [5]

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## Cost-Saving Tips

– Regular maintenance extends vehicle life

– Learn basic diagnostics to avoid unnecessary repairs

– Select certified components when OEM prices prohibitive [7]