## Typical Automotive DTCs

### P0420 Emissions Control Malfunction

– Common Causes:

Faulty oxygen sensor [1]

– Suggested Repairs:

Diagnose fuel trim https://carautorepair.site/

### P0171 Air-Fuel Ratio Error

– Potential Issues:

Vacuum leaks

– Troubleshooting Process:

Check fuel pressure [1][7]

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## Auto Repair Terminology

### Electronic Braking System

– Function: Enables safe braking [7]

### Engine Management Unit

– Role: Controls ignition timing [7]

### Powertrain Elements

– Includes: Differential [7]

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## Repair Process Steps

1. **Initial Diagnosis**:

Scan DTCs

2. **System Verification**:

Check voltage

3. **Component Installation**:

Follow torque specs

4. **Final Quality Check**:

Test drive vehicle

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## Essential Tools

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

|—|—|—|

| Code Reader | Innova | Retrieve DTCs |

| Physical Equipment | Smoke machine | Component repair |

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## Service Information References

### Mechanical Information System

– Features:

Component locations [8]

OEM specifications

### Smartphone Tools

– Vehicle Service App:

Component testing guides [5]

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## Budget Repair Strategies

– Regular maintenance extends vehicle life

– Understand DTC meanings to prevent mechanic overselling

– Use aftermarket parts when OEM prices prohibitive [7]