Ive been having a problem with my check engine light. It comes on randomly it seems, while im driving...however when I shut off the engine, it goes out.... like isnt on when I start it again. Therefore it is pretty hard to check the fault codes, since the CPU isnt storing a code in it to check. Ive checked the grounds and conections and such..... so Im stumped... any ideas?

 

codes should still be stored even if light goes off. Turn key to on - off - on - off - on in that sequence in less than 5 seconds then start counting the flashes for codes. There is a 4 second delay between the two digit codes. code 55 indicates end of test. If any codes are flashed prior to 55 then thats your problem. Code 12 indicates the battery was disconnected within last 50 starts of the engine.