## Common Diagnostic Trouble Codes

### P0420 Catalytic Converter Issue

– Common Causes:

Worn catalytic converter [1]

– Recommended Fixes:

Repair exhaust system https://carautorepair.site/

### P0171 Air-Fuel Ratio Error

– Potential Issues:

Vacuum leaks

– Diagnostic Steps:

Check fuel pressure [1][7]

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## Car Maintenance Terms

### Electronic Braking System

– Function: Prevents wheel lockup [7]

### Vehicle Computer System

– Responsibility: Controls ignition timing [7]

### Powertrain Elements

– Contains: Drive axles [7]

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## Mechanical Fixing Workflow

1. **Symptom Assessment**:

Scan DTCs

2. **Part Evaluation**:

Check voltage

3. **Defective Unit Swap**:

Clear error codes

4. **Post-Repair Verification**:

Test drive vehicle

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## Essential Tools

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

|—|—|—|

| Diagnostic Scanner | BlueDriver | Retrieve DTCs |

| Physical Equipment | Smoke machine | Electrical testing |

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## Service Information References

### Mechanical Information System

– Features:

TSB access [8]

OEM specifications

### Smartphone Tools

– Vehicle Service App:

Component testing guides [5]

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## Cost-Saving Tips

– Regular maintenance avoids costly repairs

– Master code scanning to prevent mechanic overselling

– Select certified components when OEM prices prohibitive [7]