Toyota Repair: 1996 toyota 4runner limited 3.4 automatic, toyota 4runner, torque converter

Question
Trans was just replaced runs ok for 5 to 7 miles then quits. turn it off let it sit restart it and it runs fine for even less clicks. check engine lite is on I know how to reset it. Trans oil smells burnt. My guess is solenoids aren't working because torque converter was not replaced and dirty oil from last trans was not cleaned out properly.??

Also possible alternator battery problem will have to be done too.

Is ecm check engine light telling me that it is trans problem? Or faulty ecm part of the problem?

Thank You

Answer
Have an Autozone or other major autoparts stored connect the diagnostic tool to see what trouble codes are actually in the computer, they do this at no charge then let me know the code numbers. The transmission oil should not smell burned it's an indication of internal pressure loss and slipping clutches.  Do you have any kind of warranty on the transmission? The torque converter should have been replaced or flushed at the time the trans was replaced.