On two occasions, roughly 10 days apart, my 2001 Ford Focus Automatic (214,000 miles), experienced a notable jolt, which was accompanied by the ‘automatic transaxle’ light illuminating, along with the car seeming to slip into neutral. The light stayed on for maybe 1 to 3 seconds, after which the car returned to normal. So what gives?
Both times this happened was on the freeway cruising at 60 mph. The first time was when I went over a large bump, but the second time I was just at a constant speed with no bump.
The car has been to my mechanic today who has told me that there are no codes in the computer, and he is unable to find anything that may have caused this. In every other respect the car runs great, shifts smoothly. No problems.
Has anyone ever experienced anything similar? I am a little reluctant to drive the car now as one thing is for sure, this will happen again. All advice appreciated.
As @db4690 noted, it’s possible that your shop’s scanning equipment isn’t up to the job. A local and reputable transmission shop would probably be a good stop.
Off hand, without any codes to work with and given the somewhat random and “self-healing” nature of the issue, I’d say that you have something like a loose ground. That could be directly for transmission controls or some sensor important to transmission control (e.g. speed sensor) . I would clean up all of my main power connections (both ends of the battery cables) and clean and tighten every ground you can.
I did have a couple of episodes in a car once where a bump in the road could would occasionally send my speedometer flippy. I’d be cruising at 70, hit a bump, the speedo would dive and the transmission would suddenly downshift (this did not make the engine happy as it tends to send it to the rev limiter). It did turn out to be a loose grounding block at my battery. Sometimes it’s as simple as that.