Code 12 is the standard code, telling you that you are performing the code
retrieval procedure correctly. Code 12 (1 long flash, followed by 2 shorter
flashes) will be displayed 3 times, then the car will display any other
codes 3 times, and it will return to Code 12 when it's done. If all you are
getting is Code 12, there isn't a code stored.
Here is a link that may help:
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