Possible causes

– Faulty Transmission Control Module (TCM)
– Transmission Control Module (TCM) harness is open or shorted
– Transmission Control Module (TCM) circuit poor electrical connection

Tech notes

There is a service bulletin for a various Nissan Models with the RE5R05A transmission.
Factory Nissan Service Bulletin OBDII Code P1702

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)

P1702 NISSAN Description

The Transmission Control Module (TCM) consists of a microcomputer and connectors for signal input and output and for power supply. The TCM controls the A/T.