'93 TS, 3800
Was at steady highway speed, about 105 km/h, in 4th + TCC applied...and progressively, within about 2 or 3 seconds, TCC released. COntinued in 4th, cruise control still operative, no code. I continued the run to destination, about 5 miles ahead. ON the return leg, TCC never applied. All 4 gears + cruise control continued normal operation.
Most causes in the book relate to internal failure....O-rings, seals...and the like.....or, command failure from the PCM. THis last one is simple to verify, as it is possible to bypass the PCM and provide a solid ground to either or both TCC solenoids (apply and PWM).
www.avigex.ca/xport/transaxle.jpg
NOt a priority at this time as winter is a deterrent to such initiatives and I use the car just occasionally....but I will report findings when time comes.