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Home >> Nissan-Datsun >> 2011 >> Quest SV >> Repair and Diagnosis >> Engine Performance >> Testing & Diagnosis >> Engine Control System - Introduction >> System Description >> System >> Cooling Fan Control >> COOLING FAN CONTROL : System Description >> System Description

System Description

The ECM controls the cooling fan corresponding to the vehicle speed, engine coolant temperature, refrigerant pressure, and air conditioner ON signal. The control system has 4-step control [HIGH/MIDDLE/LOW/OFF].

Cooling Fan Operation

Fig 1: Cooling Fan Operation Chart
G07051109Courtesy of NISSAN MOTOR CO., U.S.A.

Cooling Fan Relay Operation

The ECM controls cooling fan relays in the IPDM E/R through CAN communication line.

COOLING FAN RELAY OPERATION CHART

Cooling fan speed Cooling fan relay
1 2 3
Stop (OFF) OFF OFF OFF
Low (LOW) ON OFF OFF
Middle (MID) OFF ON OFF
High (HI) OFF ON ON