[Eldos4GiG]

Eldo suddely began running very rough this morning. "Service Engine Soon" indicator is "On". Check codes with "Off" & "Warmer" buttons pressed, indicated no codes as far as I can tell. Disconnected battery momentarilly. Still rough, indicator still comes on. Question: does the "Service Engine Soon" indicator mean ther are codes present? May they are there, in "History" but I did not see them?
BTW: The car ran great before being parked for about 30 hours, outside temperature was 70 degrees. This morning, temp was 40 degrees, the 1st chilly day in about 7 months, if that has any bearing on why it is so rough now. She almost will not start.
Thanks,
~GiG~

 

[CadillacSTS42005]

could be a battery issue my batt died i had to jump it and it ran hard and rough charging the battery back up

 

[Krashed989]

Eldo suddely began running very rough this morning. "Service Engine Soon" indicator is "On". Check codes with "Off" & "Warmer" buttons pressed, indicated no codes as far as I can tell. Disconnected battery momentarilly. Still rough, indicator still comes on. Question: does the "Service Engine Soon" indicator mean ther are codes present? May they are there, in "History" but I did not see them?
BTW: The car ran great before being parked for about 30 hours, outside temperature was 70 degrees. This morning, temp was 40 degrees, the 1st chilly day in about 7 months, if that has any bearing on why it is so rough now. She almost will not start.
Thanks,
~GiG~

The On Board Diagnostics only displays about 90% of the codes. The other 10%, you need a scanner tool to see them and a FSM to know what they mean. Also, yes, when the check engine light comes on it means there is stored code(s). Disconnecting the battery cable will clear the codes and may create another one.

 

[Eldos4GiG]

You guys ROCK! Questions answered so fast! Yes, I had left my Sirius Satellite unit on overnight Monday, Batt = 11.5V. Charged a few hrs, started ok, drove around, Batt = 14V.
Looks like there ARE hidden Codes :banghead: . Dang, off to dealer for this & RKE...
Thanks to ALL!
~GiG~

 

[zonie77]

Any code that lights the SES light should not be "hidden". There are non emission related codes that might be. Let us know what the dealer tells you.