there are total of 4 speed sensors, one in each wheel assembly, each one is responsible for certain portions of the car functions, all together working with the ABS module... none of the speed sensors will trip the service engine soon light, it would first trip the tranny failsafe mode and then it can trip the engine light - the cascading effect of one failing component triggering more events...

with this type of an issue, you should diagnose the car with a computer, as the check engine light has set errors in the memory that need to be read and rectified... while a speed sensor might be the original issue, without proper diagnostics you are shooting in the dark in the "under-the-bed-monsters" - you never know if there is a monster, and if there is one, if you hit it...

and a word on chinese speed sensors - it has been established on this forum, that certain items do not warrant buying chinese knock-offs, and the speed sensors fall into that category... too many folks bought the knock-offs, just to dump them and buy the OE...