1999 Honda Accord A/C Changing Cycles on own

1999 HONDA ACCORD
60,000 MILES • 4 CYL • AWD • AUTOMATIC
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JAMIEO
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  • 2 POSTS
When my A/C is operating, suddenly it starts cycling through different modes. Instead of blowing out the vents, it starts blowing upward like I changed it to defrost. Then it will start blowing down like I changed it to floor only. Do you think this is an electrical problem? Possible fuse problem? Or Switch problem. It is really hot here and I have an infant so I need to fix this ASAP and hopefully it won't cost a lot.
Jun 23, 2009 at 11:45 PM
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KHLOW2008
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  • 41,814 POSTS
Hi jamieo, Thank you for the donation. Problem is likely to be the control panel that is faulty. If your vehicle is equipped with Auto HAVC, try to get into diagnostic mode to see if there are any fault codes stored. Here are the procedures. Perform the test and see if any error codes are stored. ENTERING SELF-DIAGNOSTICS 1. Turn ignition switch to ON position. Set temperature control dial to maximum cooling, then slowly to maximum hot. After one minute, press AUTO and then the OFF button. Simultaneously press AUTO and OFF buttons. 2. If any problem exists in the system when the buttons are depressed, the temperature indicator will light up the segment corresponding to the error code. The temperature indicator will then alternate every second between displaying "88" (all segments lit) and the diagnostic trouble code segment. See Fig. 7 . If system is okay, segments will not light up. NOTE: Fault information is not retained in memory. In case of multiple problems, appropriate indicator lights will light up. If indicator lights "A","C","E","G","I" and "L" light up at same time, common ground for sensors may be open.


https://images.2carpros.com/forum/automotive_pictures/192750_ACDiagnostic99AccordFig07_1.jpg

Perform the above and let me know what you find.
Jun 24, 2009 at 8:45 AM
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JAMIEO
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The A/C apparently is not automatic. It has knobs to adjust fan speed and temperature setting. Could it possibly be that a fan under the hood stops running and the control panel goes crazy?
Jun 24, 2009 at 7:17 PM
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KHLOW2008
  • CAR REPAIR CONTRIBUTOR
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No, if it is a fuse or fan problem, it would not cause the control panel to self adjust repeatedly. I have the manual system diagnostic here for you to check.


https://images.2carpros.com/forum/automotive_pictures/192750_ACSelfDiag99Accord01_1.jpg


https://images.2carpros.com/forum/automotive_pictures/192750_ACSelfDiag99AccordFig6_1.jpg

Jun 25, 2009 at 9:17 AM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.