### P0420 Catalyst System Efficiency Below Threshold
– Typical Sources:
Exhaust leaks [1]
– Common Solutions:
Diagnose fuel trim https://carautorepair.site/
### P0171 Fuel Mixture Imbalance
– Possible Defects:
Fuel delivery problems
– Testing Procedure:
Check fuel pressure [1][7]
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## Car Maintenance Terms
### Electronic Braking System
– Function: Maintains steering control [7]
### Vehicle Computer System
– Role: Controls ignition timing [7]
### Transmission System Parts
– Includes: Transmission [7]
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## Service Procedure Stages
1. **Initial Diagnosis**:
Perform visual inspection
2. **Component Testing**:
Check voltage
3. **Defective Unit Swap**:
Clear error codes
4. **Final Quality Check**:
Confirm warning light reset
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## Critical Instruments
| **Tool Type** | **Examples** | **Purpose** |
|—|—|—|
| OBD-II Tool | Autel | Live data streaming |
| Physical Equipment | Multimeter | Component repair |
—
## Service Information References
### Auto Repair Source
– Capabilities:
TSB access [8]
OEM specifications
### Digital Assistants
– Vehicle Service App:
Component testing guides [5]
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## Cost-Saving Tips
– Routine checkups prevents major failures
– Understand DTC meanings to prevent mechanic overselling
– Select certified components when OEM prices prohibitive [7]