### P0420 Emissions Control Malfunction
– Typical Sources:
Worn catalytic converter [1]
– Recommended Fixes:
Diagnose fuel trim https://carautorepair.site/
### P0171 Air-Fuel Ratio Error
– Potential Issues:
Vacuum leaks
– Testing Procedure:
Smoke test intake [1][7]
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## Vehicle Service Vocabulary
### Electronic Braking System
– Function: Enables safe braking [7]
### Vehicle Computer System
– Responsibility: Manages fuel injection [7]
### Drivetrain Components
– Contains: Transmission [7]
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## Repair Process Steps
1. **Initial Diagnosis**:
Scan DTCs
2. **System Verification**:
Test continuity
3. **Parts Replacement**:
Use OEM parts
4. **Final Quality Check**:
Confirm warning light reset
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## Essential Tools
| **Tool Type** | **Examples** | **Purpose** |
|—|—|—|
| Diagnostic Scanner | Innova | Live data streaming |
| Mechanical Tools | Smoke machine | Component repair |
—
## Repair Documentation Sources
### Mechanical Information System
– Capabilities:
Wiring diagrams [8]
OEM specifications
### Digital Assistants
– Vehicle Service App:
ECU pinouts [5]
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## Affordable Maintenance Advice
– Routine checkups extends vehicle life
– Master code scanning to prevent mechanic overselling
– Select certified components when OEM prices prohibitive [7]