## Typical Automotive DTCs

### P0420 Catalyst System Efficiency Below Threshold

– Common Causes:

Faulty oxygen sensor [1]

– Common Solutions:

Replace catalytic converter https://carautorepair.site/

### P0171 System Too Lean

– Possible Defects:

Faulty MAF sensor

– Troubleshooting Process:

Inspect injectors [1][7]

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## Vehicle Service Vocabulary

### Electronic Braking System

– Purpose: Prevents wheel lockup [7]

### Engine Management Unit

– Role: Monitors sensors [7]

### Drivetrain Components

– Contains: Drive axles [7]

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## Mechanical Fixing Workflow

1. **Symptom Assessment**:

Scan DTCs

2. **Part Evaluation**:

Test continuity

3. **Component Installation**:

Use OEM parts

4. **Post-Repair Verification**:

Ensure proper operation

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## Essential Tools

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

|—|—|—|

| Code Reader | Autel | Live data streaming |

| Mechanical Tools | Multimeter | Component repair |

—

## Technical Data Resources

### Auto Repair Source

– Features:

Component locations [8]

Factory repair procedures

### Mobile Applications

– Vehicle Service App:

ECU pinouts [5]

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## Budget Repair Strategies

– Preventative service prevents major failures

– Understand DTC meanings to prevent mechanic overselling

– Select certified components when OEM prices prohibitive [7]