QuestionI noticed yestersday that the heater/AC unit was slowly blinking, it would be on, then shut down, and come on again. I would press "off," then "auto," then adjust the temp, and it would stay on. What does this indicate, a loose wire? Does the unit in the console need to be replaced? What do you estimate the cost to repair for a competent do-it-yourselfer? Thanks!
AnswerHi Mark,
You didn't mention the year of the vehicle, but I can tell you about what might be wrong, based on the '94 manual. I expect to receive a manual for '98 in a few days which I purchased at auction on eBay which may have other info.
According to the '94, the display will blink that way when the unit has entered a self-diagnostic mode. You can prompt that by simultaneously pushing at first, second, and fourth buttons on the top row and holding them in until the unit starts to blink (those are the floor, mix, and defrost). Once it starts to blink you can release the buttons and wait for any two digit numbers to appear on the screen which are codes for various possible faults (23-36). If no numbers appear the blinking will eventually stop and it will return to normal. If numbers appear, note them and press the panel with the arrow showing the instrument panel distribution (first one on the bottom row) to cycle through the numbers, if more than one, and then it should return to the normal mode.
I have heard of these units doing the diagnostic test routine seemingly on their own. So play around with that idea. If you can get it back to the normal mode I wouldn't worry about it unless it becomes so frequent as to be detrimental to the normal function of the system.
Other than that I know of no other cause of display blinking in the ATC control head. I will look closely at the '98 manual when it arrives. If you find something interesting or want to ask again at the end of the week I may have more info.
Roland
