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DTC 12




Code 12


The first code to display should be code 12. This indicates that the self-diagnostics are functioning and is not a trouble code. The code 12 display is a flash followed by a short pause, then two flashes followed by a longer pause. If other codes are present, they will display in the same manner after code 12 has flashed three times. For example, the code 23 display is two flashes followed by a short pause, then three flashes followed by a longer pause. Each stored code is displayed three times, starting with the lowest in numerical order. Code 12 will repeat when all codes have shown. If no codes are stored, code 12 will display repeatedly until Diagnostic mode is exited by removal of the ALDL jumper wire. Remove the jumper wire before attempting to start the engine.