## Typical Automotive DTCs

### P0420 Catalytic Converter Issue

– Frequent Reasons:

Faulty oxygen sensor [1]

– Recommended Fixes:

Diagnose fuel trim https://carautorepair.site/

### P0171 Air-Fuel Ratio Error

– Possible Defects:

Faulty MAF sensor

– Diagnostic Steps:

Check fuel pressure [1][7]

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## Car Maintenance Terms

### ABS (Anti-Lock Brake System)

– Function: Maintains steering control [7]

### Engine Management Unit

– Role: Manages fuel injection [7]

### Transmission System Parts

– Contains: Transmission [7]

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## Repair Process Steps

1. **Symptom Assessment**:

Perform visual inspection

2. **System Verification**:

Test continuity

3. **Defective Unit Swap**:

Follow torque specs

4. **Post-Repair Verification**:

Confirm warning light reset

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## Critical Instruments

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

|—|—|—|

| Diagnostic Scanner | Innova | Live data streaming |

| Hand Instruments | Torque wrench | Component repair |

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## Repair Documentation Sources

### Mechanical Information System

– Capabilities:

TSB access [8]

OEM specifications

### Digital Assistants

– Vehicle Service App:

Component testing guides [5]

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## Cost-Saving Tips

– Regular maintenance extends vehicle life

– Master code scanning to prevent mechanic overselling

– Select certified components when OEM prices prohibitive [7]