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.
Without "SCAN" Tool
The ECM stores component failure information for the CCC system under a related trouble code which can be recalled for diagnosis and repair. When recalled, these codes will be displayed by flashes of the "SERVICE ENGINE SOON" light. Trouble codes are displayed starting with the lowest numbered code. Only codes that represent a definite malfunction will be shown.
Trouble codes are read by counting flashes of the "SERVICE ENGINE SOON" light, or by reading output on a diagnostic tool ("SCAN" TOOL) connected to the ALDL connector. These special tools are faster and more accurate, but are not mandatory.
If a "SCAN" tool is not available, read the flashes of the "SERVICE ENGINE SOON" lamp. For example, "FLASH", "FLASH", pause, "FLASH", longer pause, identifies "21". The first flashes are the first digit of the code, second flashes are the second digit.
NO RELATED
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:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.