## Frequent Vehicle Error Codes

### P0420 Catalyst System Efficiency Below Threshold

– Frequent Reasons:

Exhaust leaks [1]

– Common Solutions:

Diagnose fuel trim https://carautorepair.site/

### P0171 Air-Fuel Ratio Error

– Likely Problems:

Vacuum leaks

– Troubleshooting Process:

Check fuel pressure [1][7]

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## Vehicle Service Vocabulary

### Skid Prevention Technology

– Function: Prevents wheel lockup [7]

### Engine Management Unit

– Responsibility: Manages fuel injection [7]

### Drivetrain Components

– Includes: Drive axles [7]

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## Repair Process Steps

1. **Symptom Assessment**:

Scan DTCs

2. **System Verification**:

Check voltage

3. **Parts Replacement**:

Follow torque specs

4. **Final Quality Check**:

Confirm warning light reset

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## Critical Instruments

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

|—|—|—|

| Diagnostic Scanner | BlueDriver | Live data streaming |

| Physical Equipment | Torque wrench | Component repair |

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## Repair Documentation Sources

### Mechanical Information System

– Features:

TSB access [8]

Factory repair procedures

### Digital Assistants

– Vehicle Service App:

Component testing guides [5]

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## Affordable Maintenance Advice

– Regular maintenance prevents major failures

– Learn basic diagnostics to prevent mechanic overselling

– Use aftermarket parts when OEM prices prohibitive [7]