Possible causes

– Throttle Control Motor Relay harness is open
– Throttle Control Motor Relay circuit poor electrical connection
– Faulty Throttle Control Motor Relay

Symptoms

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

P2100 NISSAN Description

Power supply for the throttle control motor is provided to the Engine Control Module (ECM) via throttle control motor relay. The throttle control motor relay is ON/OFF controlled by the ECM. When the ignition switch is turned ON, the ECM sends an ON signal to throttle control motor relay and battery voltage is provided to the ECM. When the ignition switch is turned OFF, the ECM sends an OFF signal to throttle control motor relay and battery voltage is not provided to the ECM.