### P0420 Catalyst System Efficiency Below Threshold
– Frequent Reasons:
Exhaust leaks [1]
– Recommended Fixes:
Repair exhaust system https://carautorepair.site/
### P0171 System Too Lean
– Possible Defects:
Vacuum leaks
– Diagnostic Steps:
Check fuel pressure [1][7]
—
## Vehicle Service Vocabulary
### Electronic Braking System
– Purpose: Prevents wheel lockup [7]
### ECM/ECU (Engine Control Module)
– Role: Controls ignition timing [7]
### Powertrain Elements
– Contains: Differential [7]
—
## Service Procedure Stages
1. **Problem Identification**:
Conduct road test
2. **System Verification**:
Measure resistance
3. **Parts Replacement**:
Follow torque specs
4. **Final Quality Check**:
Ensure proper operation
—
## Critical Instruments
| **Tool Type** | **Examples** | **Purpose** |
|—|—|—|
| Code Reader | Innova | Retrieve DTCs |
| Mechanical Tools | Multimeter | Component repair |
—
## Repair Documentation Sources
### Auto Repair Source
– Features:
Component locations [8]
Technical illustrations
### Mobile Applications
– Auto Repair Documents:
Electrical diagrams [5]
—
## Budget Repair Strategies
– Preventative service extends vehicle life
– Master code scanning to prevent mechanic overselling
– Use aftermarket parts when OEM prices prohibitive [7]
