I know this subject has been blogged to death...but mine seems a little different, and once users typically fix the issue, rarely do they come back and tell us WHAT fixed the problem
Here's what my 2006 Mustang GT is doing (100% factory other than a K& N cool air intake system that was donated to me).
While riding down the road about 6 weeks ago, I noticed my ABS light and TCS light on...all other gauges were working perfectly. I tried to roll down the windows, but they wouldn't work. This went on for about 15 seconds while on the expressway.
Nothing happened for another 2 weeks, then it happened again while driving down a 2-lane heading to work. The only difference this time is the system displayed "Checking Charging System" towards the end of the lights being displayed.
This has happened about once a week for the last 6 weeks, but this week it has happened about every other day, and today it happened 3 times on the way to work.
When this happens, the lights come on the dash (ABS, TCS, and some others), The BATTERY Gauge DOES NOT DROP, and neither does the RPM gauge or the speedo. I have had AZ run tests on the battery and alternator and they are fine...but I can't make the car do it while they are testing either.
Is this a problem of the alternator coming and going? Or, is this a computer/ignition issue? I have not replaced anything in my car in the last 6 weeks...except tires and oil. Everything is factory under the hood except for the intake system mentioned above.
I do not have the $300 to buy a new alternator to find out later that wasn't it. Has anyone had the same exact issue as me? I have not seen a post where the battery gauge and the speedo/RPM gauge doesn't move. When the car is doing it's thing, the car runs perfectly fine. It has happened at expressway speeds, and 2-lane speeds (yes, I DO drive slower on 2-lanes
I am at a loss as to what is going on. Again, I do not want to drop $250-300 on a new alternator if that is not the issue! I am desperate for an answer here. Luckily, I am mechanically inclined, so I can do the install/testing...if install/testing is needed?