Advanced
5 min read
· OBD Code Mastery
DTC Triage: Red, Yellow, Green Severity System
Not all codes are emergencies. Learn which DTC codes mean pull over now, schedule within 48 hours, or address at next PM.
Key Facts
- RED: Flashing check engine, U-codes, oil/coolant critical — pull over now
- YELLOW: Steady CEL with symptoms, misfires, ABS — schedule 48 hours
- A flashing check engine light = active misfire, fire risk — no exceptions
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