Symptoms of a Bad Transmission Control Module (TCM) 

Symptoms of a bad transmission control module (TCM) and how to test if it has gone bad.
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What is the Transmission Control Module (TCM)?
The TCM uses various sensors to choose the best gear for the vehicle to use at any given time.
When the TCM has a problem, the shifting of the vehicle will also have a problem.
Symptoms of a Bad Transmission Control Module (TCM)
Limp Mode
Hard Shifting
Delayed shifting
Trouble downshifting
Stuck in gear
Not downshifting correctly
Transmission overheating
Shifts unexpectedly
Engine roars loudly and has difficulty shifting
How To Tell if TCM Has Failed?
Read transmission error codes.
Check fuses and relays.
Inspect wiring and TCM module for any damage.
By using this information user assumes all risk of use.