## Common Diagnostic Trouble Codes

### P0420 Emissions Control Malfunction

– Frequent Reasons:

Worn catalytic converter [1]

– Common Solutions:

Diagnose fuel trim https://carautorepair.site/

### P0171 Air-Fuel Ratio Error

– Likely Problems:

Vacuum leaks

– Testing Procedure:

Check fuel pressure [1][7]

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## Car Maintenance Terms

### ABS (Anti-Lock Brake System)

– Function: Enables safe braking [7]

### ECM/ECU (Engine Control Module)

– Role: Monitors sensors [7]

### Transmission System Parts

– Includes: Differential [7]

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## Repair Process Steps

1. **Initial Diagnosis**:

Perform visual inspection

2. **Part Evaluation**:

Test continuity

3. **Component Installation**:

Use OEM parts

4. **System Validation**:

Test drive vehicle

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## Essential Tools

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

|—|—|—|

| Diagnostic Scanner | Autel | Live data streaming |

| Hand Instruments | Smoke machine | Electrical testing |

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## Technical Data Resources

### Mechanical Information System

– Capabilities:

Component locations [8]

Factory repair procedures

### Digital Assistants

– Vehicle Service App:

Electrical diagrams [5]

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## Affordable Maintenance Advice

– Routine checkups avoids costly repairs

– Learn basic diagnostics to prevent mechanic overselling

– Install quality alternatives when OEM prices prohibitive [7]