## Frequent Vehicle Error Codes

### P0420 Emissions Control Malfunction

– Typical Sources:

Exhaust leaks [1]

– Suggested Repairs:

Diagnose fuel trim https://carautorepair.site/

### P0171 Air-Fuel Ratio Error

– Possible Defects:

Faulty MAF sensor

– Testing Procedure:

Smoke test intake [1][7]

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## Auto Repair Terminology

### Skid Prevention Technology

– Purpose: Prevents wheel lockup [7]

### Engine Management Unit

– Responsibility: Monitors sensors [7]

### Drivetrain Components

– Includes: Drive axles [7]

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## Service Procedure Stages

1. **Initial Diagnosis**:

Perform visual inspection

2. **Component Testing**:

Test continuity

3. **Parts Replacement**:

Follow torque specs

4. **Final Quality Check**:

Confirm warning light reset

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## Necessary Equipment

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

|—|—|—|

| Code Reader | Innova | Retrieve DTCs |

| Physical Equipment | Smoke machine | Electrical testing |

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## Repair Documentation Sources

### Vehicle Service Database

– Features:

Wiring diagrams [8]

Factory repair procedures

### Digital Assistants

– Vehicle Service App:

ECU pinouts [5]

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## Affordable Maintenance Advice

– Routine checkups prevents major failures

– Understand DTC meanings to prevent mechanic overselling

– Use aftermarket parts when budget constrained [7]