Probable Causes

WARNING: This page is about a different car, the 2014 Mitsubishi Outlander. However, it is still accessible from the selected car via links, so may be relevant.

Non-genuine device installation: TCM voltage drop
Improper fixing of the electric wiring, poor insertion of the connector, poor contact of the inside PIN
Poor adjustment of transmission range switch
Failure of the transmission range switch main unit
Malfunction of the TCM
TCM power supply or ground failure
A/T failure: Hydraulic system (valve body assembly), driving force transaxle system (clutch/brake)