### P0420 Catalytic Converter Issue
– Common Causes:
Faulty oxygen sensor [1]
– Common Solutions:
Repair exhaust system https://carautorepair.site/
### P0171 Air-Fuel Ratio Error
– Possible Defects:
Vacuum leaks
– Diagnostic Steps:
Check fuel pressure [1][7]
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## Vehicle Service Vocabulary
### Electronic Braking System
– Function: Prevents wheel lockup [7]
### ECM/ECU (Engine Control Module)
– Role: Manages fuel injection [7]
### Drivetrain Components
– Contains: Drive axles [7]
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## Mechanical Fixing Workflow
1. **Problem Identification**:
Scan DTCs
2. **System Verification**:
Test continuity
3. **Parts Replacement**:
Use OEM parts
4. **Post-Repair Verification**:
Confirm warning light reset
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## Critical Instruments
| **Tool Type** | **Examples** | **Purpose** |
|—|—|—|
| Diagnostic Scanner | Innova | Retrieve DTCs |
| Mechanical Tools | Smoke machine | Electrical testing |
—
## Repair Documentation Sources
### Auto Repair Source
– Features:
Wiring diagrams [8]
OEM specifications
### Smartphone Tools
– Vehicle Service App:
Component testing guides [5]
—
## Cost-Saving Tips
– Routine checkups avoids costly repairs
– Understand DTC meanings to avoid unnecessary repairs
– Use aftermarket parts when OEM prices prohibitive [7]
