Find the Assembly Line Data Link, on Bottom of Dash to the Left, under Steering Wheel. This Little Black Plastic Plug-in, will have Six Square Holes in the Top Row, and Six in the Bottom Row. All of these are not used. You just need to Jump between the Upper Right, which is A, and the next One to the Left, which is B. This is done with the Ignition on, and the Engine not running. After it flashes the Code 12 Three times, it will show you all of the stored Codes.
Code 12 just means that the ECM is going into diagnostic mode, this is NOT a trouble code! Code 12 should blink a couple of times pause then blink your trouble codes if you have any. If you have no trouble codes, it will resume to blink code 12 again.
fuel pump low voltage
It means the crankshaft and camshaft sensors arent correlated. Which basically means your distributor isnt timed correctly.
There is a problem with your airbag system. Some vehicles will blink to display a diagnostic trouble code. For example 10 flashes, pause and 3 flashes, will indicate the trouble code 13.
DTC code 81, 2-3 shift solenoid circuit fault. DTC code 12, indicates the diagnostic system is working.
knock sensor
it a transmission slipping code
call the dealer and get the code....
Diagnostic trouble code
need to run diagnostic should throw a code is check engine light on?
Code p0507 2001 chevy s10 replace upper intake, iac, tps still have problem
System to rich (bank 2)