Possible causes

– Faulty Direct Clutch Solenoid Valve
– Direct Clutch Solenoid Valve harness is open or shorted
– Direct Clutch Solenoid Valve 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 P1764

Symptoms

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

P1764 NISSAN Description

Direct clutch solenoid valve is controlled by the Transmission Control Module (TCM) in response to signals sent from the PNP switch, vehicle speed sensor and accelerator pedal position sensor (throttle position sensor). Gears will then be shifted to the optimum position.