### P0420 Emissions Control Malfunction
– Frequent Reasons:
Worn catalytic converter [1]
– Suggested Repairs:
Diagnose fuel trim https://carautorepair.site/
### P0171 Fuel Mixture Imbalance
– Likely Problems:
Faulty MAF sensor
– Testing Procedure:
Check fuel pressure [1][7]
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## Vehicle Service Vocabulary
### ABS (Anti-Lock Brake System)
– Function: Prevents wheel lockup [7]
### ECM/ECU (Engine Control Module)
– Role: Manages fuel injection [7]
### Transmission System Parts
– Contains: Drive axles [7]
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## Mechanical Fixing Workflow
1. **Symptom Assessment**:
Conduct road test
2. **Part Evaluation**:
Test continuity
3. **Defective Unit Swap**:
Use OEM parts
4. **System Validation**:
Test drive vehicle
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## Essential Tools
| **Tool Type** | **Examples** | **Purpose** |
|—|—|—|
| Diagnostic Scanner | Innova | Live data streaming |
| Hand Instruments | Torque wrench | Component repair |
—
## Repair Documentation Sources
### Mechanical Information System
– Features:
Wiring diagrams [8]
OEM specifications
### Digital Assistants
– Auto Repair Documents:
ECU pinouts [5]
—
## Affordable Maintenance Advice
– Regular maintenance extends vehicle life
– Understand DTC meanings to prevent mechanic overselling
– Use aftermarket parts when budget constrained [7]
