## Typical Automotive DTCs

### P0420 Emissions Control Malfunction

– Frequent Reasons:

Faulty oxygen sensor [1]

– Common Solutions:

Replace catalytic converter https://carautorepair.site/

### P0171 Air-Fuel Ratio Error

– Likely Problems:

Vacuum leaks

– Troubleshooting Process:

Smoke test intake [1][7]

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## Vehicle Service Vocabulary

### Electronic Braking System

– Purpose: Maintains steering control [7]

### Vehicle Computer System

– Responsibility: Controls ignition timing [7]

### Powertrain Elements

– Includes: Differential [7]

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## Mechanical Fixing Workflow

1. **Symptom Assessment**:

Scan DTCs

2. **Component Testing**:

Measure resistance

3. **Defective Unit Swap**:

Follow torque specs

4. **Post-Repair Verification**:

Test drive vehicle

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## Critical Instruments

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

|—|—|—|

| OBD-II Tool | Innova | Retrieve DTCs |

| Physical Equipment | Multimeter | Electrical testing |

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## Repair Documentation Sources

### Vehicle Service Database

– Capabilities:

Wiring diagrams [8]

OEM specifications

### Digital Assistants

– Auto Repair Documents:

Component testing guides [5]

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## Cost-Saving Tips

– Regular maintenance prevents major failures

– Understand DTC meanings to prevent mechanic overselling

– Install quality alternatives when budget constrained [7]