## Common Diagnostic Trouble Codes

### P0420 Emissions Control Malfunction

– Typical Sources:

Faulty oxygen sensor [1]

– Suggested Repairs:

Diagnose fuel trim https://carautorepair.site/

### P0171 Air-Fuel Ratio Error

– Likely Problems:

Fuel delivery problems

– Testing Procedure:

Inspect injectors [1][7]

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## Auto Repair Terminology

### ABS (Anti-Lock Brake System)

– Function: Prevents wheel lockup [7]

### Engine Management Unit

– Responsibility: Monitors sensors [7]

### Drivetrain Components

– Includes: Transmission [7]

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## Service Procedure Stages

1. **Problem Identification**:

Perform visual inspection

2. **System Verification**:

Measure resistance

3. **Defective Unit Swap**:

Follow torque specs

4. **Final Quality Check**:

Confirm warning light reset

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## Necessary Equipment

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

|—|—|—|

| Diagnostic Scanner | Autel | Live data streaming |

| Physical Equipment | Smoke machine | Component repair |

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## Technical Data Resources

### Vehicle Service Database

– Features:

TSB access [8]

Technical illustrations

### Digital Assistants

– Vehicle Service App:

ECU pinouts [5]

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## Budget Repair Strategies

– Routine checkups extends vehicle life

– Master code scanning to avoid unnecessary repairs

– Select certified components when OEM prices prohibitive [7]