Engine Cooling Fan Nissan Stanza III

SYSTEM TESTING

Note. Pathfinder and Pickup do not use electric cooling fans.

MAXIMA

Warm engine to operating temperature. Engage A/C clutch using A/C switch in passenger compartment. Both cooling fans should run at low speed. Disconnect coolant temperature sensor connector. Both cooling fans should run at high speed. If not, check power supplies, grounds, relays, radiator fan switches and motors. If no faults are found, check component wiring. (Scheme 2)

NX & SENTRA

Warm engine to operating temperature. Cooling fan should come on. If equipped with A/C, engage A/C clutch using A/C switch in passenger compartment. Condenser cooling fan should come on. If fans do not function as described, check power supplies, grounds, relays, radiator fan switches and motors. If no faults are found, check component wiring. (Scheme 3)and (Scheme 4).

STANZA

1. If vehicle is not equipped with A/C, warm engine to operating temperature. Cooling fan should come on. If vehicle is equipped with A/C, engage A/C clutch using A/C switch in passenger compartment. Condenser cooling fan should operate at low speed.
2. Stop engine and turn A/C off (if equipped). Disconnect coolant temperature sensor. Start engine. Both cooling fans should run at high speed. If cooling fans do not function as described, check power supplies, grounds, relays, radiator fan switches and motors. If no faults are found, check component wiring. (Scheme 5)

240SX

Warm engine to operating temperature. Engage A/C clutch using A/C switch in passenger compartment. Cooling fan should run. If cooling fan does not function as described, check power supplies, grounds, relay, radiator fan switch and motor. If no faults are found, check component wiring. (Scheme 6)

300ZX

Warm engine to operating temperature. Cooling fan should run. If cooling fan does not operate, check power supplies, grounds, relays, radiator fan switches and motors. If no faults are found, check component wiring. (Scheme 7)

FAN MOTOR

Disconnect electrical connector at fan motor. Supply battery voltage and ground to fan motor connector. Motor should run. If not, check for open or short in motor windings.

RELAYS

1. Three different cooling fan relays are used. All are found in appropriate relay box in engine compartment. They are a 4-wire double contact relay (Blue), a 4-wire toggle select relay (Black) and a 6-wire dual-function relay (Brown). (Scheme 1)
2. Test relays by supplying ground and battery voltage across the relay winding of the relay (terminals No. 1 and 2). When relay is energized, continuity should be present between terminals No. 3 and 5, and also terminals No. 6 and 7 of the Brown dual-function relay.
3. When de-energized, continuity should exist between terminals No. 4 and 5 of the Black toggling relay. Continuity should exist between terminals No. 1 and 2 of all relays.

RADIATOR FAN SWITCH (NX & SENTRA - 1.6L)

1. With coolant temperature less than rated activation temperature, check continuity across terminals of radiator fan switch. See RADIATOR FAN SWITCH TEMPERATURE TABLE. Continuity should not exist. Warm engine to operating temperature. Continuity should now exist.
2. If continuity does not exist, remove radiator fan switch. Check for coating of switch with foreign substance. Bench test switch using a thermometer, a glass or metal container filled with coolant mixture and a heat source. Check resistance at rated temperature. If switch does not function properly, replace switch.

RADIATOR FAN SWITCH TEMPERATURE

Scheme 1

Scheme 2

Scheme 3

Scheme 4

Scheme 5

Scheme 6

Scheme 7