## Frequent Vehicle Error Codes

### P0420 Catalyst System Efficiency Below Threshold

– Common Causes:

Faulty oxygen sensor [1]

– Recommended Fixes:

Repair exhaust system https://carautorepair.site/

### P0171 System Too Lean

– Possible Defects:

Vacuum leaks

– Troubleshooting Process:

Check fuel pressure [1][7]

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## Auto Repair Terminology

### ABS (Anti-Lock Brake System)

– Purpose: Prevents wheel lockup [7]

### ECM/ECU (Engine Control Module)

– Role: Monitors sensors [7]

### Powertrain Elements

– Contains: Differential [7]

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## Mechanical Fixing Workflow

1. **Problem Identification**:

Conduct road test

2. **Part Evaluation**:

Test continuity

3. **Parts Replacement**:

Use OEM parts

4. **System Validation**:

Confirm warning light reset

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## Essential Tools

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

|—|—|—|

| Code Reader | BlueDriver | Retrieve DTCs |

| Mechanical Tools | Torque wrench | Component repair |

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## Technical Data Resources

### Mechanical Information System

– Capabilities:

Component locations [8]

Factory repair procedures

### Mobile Applications

– Auto Repair Documents:

Electrical diagrams [5]

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## Budget Repair Strategies

– Preventative service prevents major failures

– Understand DTC meanings to avoid unnecessary repairs

– Install quality alternatives when OEM prices prohibitive [7]