Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Engine Controls - Tests W/Codes: Summary
If no hard fault codes (or only pass codes) are present, driveability symptoms exist or intermittent codes exist, proceed to the TESTS W/O CODES article in the ENGINE PERFORMANCE Section for diagnosis by symptom (i.e. ROUGH IDLE, NO START, etc.) or intermittent diagnostic procedures.
| Abbreviation | Color |
|---|---|
| BR | Black/Red |
| BW | Black/White |
| BY | Black/Yellow |
| G | Green |
| GB | Green/Black |
| GL | Green/Blue |
| GR | Green/Red |
| GW | Green/White |
| GY | Green/Yellow |
| Lg | Light Green |
| LgB | Light Green/Black |
| LR | Blue/Red |
| LW | Blue/White |
| LY | Blue/Yellow |
| RY | Red/Yellow |
| W | White |
| WB | White/Black |
| WR | White/Red |
| WY | White/Yellow |
| Y | Yellow |
| YL | Yellow/Blue |
| YR | Yellow/Red |
| YW | Yellow/White |
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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