### P0420 Emissions Control Malfunction
– Typical Sources:
Faulty oxygen sensor [1]
– Suggested Repairs:
Replace catalytic converter https://carautorepair.site/
### P0171 Air-Fuel Ratio Error
– Possible Defects:
Fuel delivery problems
– Testing Procedure:
Smoke test intake [1][7]
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## Auto Repair Terminology
### Electronic Braking System
– Function: Enables safe braking [7]
### Vehicle Computer System
– Role: Manages fuel injection [7]
### Transmission System Parts
– Contains: Drive axles [7]
—
## Mechanical Fixing Workflow
1. **Initial Diagnosis**:
Scan DTCs
2. **Part Evaluation**:
Measure resistance
3. **Parts Replacement**:
Follow torque specs
4. **System Validation**:
Confirm warning light reset
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## Essential Tools
| **Tool Type** | **Examples** | **Purpose** |
|—|—|—|
| Diagnostic Scanner | BlueDriver | Retrieve DTCs |
| Hand Instruments | Smoke machine | Component repair |
—
## Repair Documentation Sources
### Auto Repair Source
– Capabilities:
Component locations [8]
Factory repair procedures
### Digital Assistants
– Vehicle Service App:
ECU pinouts [5]
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## Affordable Maintenance Advice
– Regular maintenance extends vehicle life
– Learn basic diagnostics to prevent mechanic overselling
– Install quality alternatives when budget constrained [7]
