QuestionQUESTION: I have a 91' Sedan De Ville and get the A/C to turn on or the vents to open with the heater on. Was wondering if it is just a relay.
ANSWER: IS or has the check engine light ever illuminated while driving the vehicle ?.
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QUESTION: Yes, it is on now.
ANSWER: Do you know how to retrieve the codes from the computer ?.
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QUESTION: I read somewhere how to do it, but I can't find the link, so no.
Answer1. Ignition switch ON. Engine OFF.
2. Simultaneously push and hold the OFF and WARMER buttons for 3 seconds and release them.
3. Codes will appear in the form of LETTERS & NUMBERS followed by the word HISTORY or CURRENT for EACH code that displays in the fuel data display.
4. The display will stop at ECM? or PCM?
5. turn OFF ignition.
6. Tell me what codes and which are HISTORY or CURRENT.
