This will be an internal problem with the transmission, hard to say at this time if it will be electrical or mechanical. There may be a fault code in the transmission, not all codes will set a fault light. If no codes the problem probably will be mechanical, so first thing to do is see if there is a code and you can also get a check done with a factory scanner to see if the electrical solenoids are switching on and off.
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Saturday, January 6th, 2018 AT 4:05 AM