Can't read the computer when the computer is plugged into port. Is there a power relay or some type of fuse for that. I have a Cadillac Eldorado, 1997. The computer is fine.

 

Likely blown fuse...try cigar or body, but you may have to check them all. A test light should make it fairly quick to locate.

 

New Issue "Service Engine Soon" Light.
For a 2004 DTS with over 111k miles now, recent stabilizer steering column change, new plugs, recent oil change etc., when the "Service Engine Soon" light stays on, the manual says primarily to check for fuel changes which could affect the light staying on. Having none, how do you get the light off without an expensive dealer probe

 

In most areas auto parts stores will read and clear check engine light codes for free. Why?, the intent is to sell you what ever part that would set that code (O2 sensor code set....You need a new sensor....they aren't always right) They don't diagnose code generally.

 

Hi dear i have a something about engine light My car is throwing a lean code (i have a code reader) this is not an oil service light ti is a check engine light. it is a 2002 bmw 325i. i did my valve cover and shortly after got an SES light.