What year is your car and what engine? That makes a lot of difference. What the pulses should indicate is a code 12 is stored (code 55 is usually an "all clear" code, meaning that the ECU is done reading out the codes that are stored). If you got only a 55, it would mean you have no codes. 1255 means that 12 is the only code you have stored.
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What year is your car and what engine? That makes a lot of difference. What the pulses should indicate is a code 12 is stored (code 55 is usually an "all clear" code, meaning that the ECU is done reading out the codes that are stored). If you got only a 55, it would mean you have no codes. 1255 means that 12 is the only code you have stored.