Question
Subject a/c econ control not working
Question QUESTION: Hi--96 Sedan DeVille: After mechanic cleared computer codes and changed oil the a/c econ does not work. It stays on econ and will not go to A/c. This is the second time this happened after oil change. How can this be so???. First time it seemed to clear itself. A/c did work fine as did auto climate control. Any thoughts? Thank you.
ANSWER: IS or HAS the CHECK ENGINE light ever illuminated while driving the vehicle ?.
If it HAS or has NOT, Let's check for FAULT CODES via:
1. Ignition ON. Engine OFF.
2. Simultaneously push and hold the OFF and WARMER (^) buttons on your climate control panel for 3 seconds and release them.
3. CODES in the form of LETTERS & NUMBERS will appear followed by the word HISTORY or CURRENT with each code that displays.
4. The display will stop at PCM?
5. Write down these codes EXACTLY as they appear as if you were video taping them and let me know what they are.
6. Turn OFF ignition.
---------- FOLLOW-UP ----------
QUESTION: Hello--I did as you suggested but no codes or messages display. So, what is the next step? By the way, this car frequently displays messages that seem to have no basis: service transmission, brake light switch failure, etc. Check engine light comes on frequently: car has been serviced regularly, sensors renewed as needed, etc. Has 120K on it. Thanks.
ANSWER: If the check engine light comes on frequently that MUST be fault codes in the computer.
Are you looking on the fuel data screen for the codes ?.
---------- FOLLOW-UP ----------
QUESTION: Hi--Yes, I am looking at it BUT...the codes do not display. Nothing happens when I press warmer and off simultaneously. I understand that there will be fault codes. I would be pleased to see them if I could...
Any ideas? Thank you.
Answer Do you have a DIGITAL instrument cluster or an old style analog cluster ?.
I have a digital cluster
AnswerOK, repeat this CHANGED directives and tell me what happens when you perform step # 2.
. Ignition ON. Engine OFF.
2. Simultaneously push and hold the OFF and WARMER (^) (fan up) buttons on your climate control panel for 3 seconds and release them.
3. CODES in the form of LETTERS & NUMBERS will appear followed by the word HISTORY or CURRENT with each code that displays.
4. The display will stop at PCM?
5. Write down these codes EXACTLY as they appear as if you were video taping them and let me know what they are.
6. Turn OFF ignition.
