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Engine Cooling Fan: Other Nissan Quest II

Cooling Fan 13 illustrations ~4483 words

SYSTEM TESTS

Note. Cooling fan can also be diagnosed using appropriate self-diagnostic trouble shooting codes. A Diagnostic Trouble Code (DTC) is set when a cooling fan problem arises. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.

Note. ECM refers to ECCS control unit. ECM controls cooling fan operation based on inputs from coolant temperature sensor and A/C switch.

COOLING FAN CIRCUIT (ALTIMA)

  1. Check Low Speed Fan Operation Turn ignition off. Disconnect cooling fan relays No. 2 and 3. Relays are located in underhood relay box. (Scheme 3) Start engine. Set temperature lever to full cold position. Turn A/C switch and blower fan switch to ON position. Run engine at idle for several minutes. Verify cooling fan operates at low speed. If fan does not operate at low speed, go to step 3. If fan operates at low speed, go to next step.
  2. Check High Speed Fan Operation Turn ignition off. Reconnect cooling fan relays No. 2 and 3. Disconnect cooling fan relay No. 1. Turn ignition on. Turn A/C switch and blower fan switch to OFF position. Disconnect Engine Coolant Temperature (ECT) sensor harness connector. Connect a 150-ohm resistor across ECT sensor harness connector terminals. Restart engine. Verify cooling fan operates at high speed. If fan does not operate at high speed, go to step 7. If fan operates at high speed, check cooling system for leaks, radiator cap pressure and thermostat operation. Repair as necessary. Inspect ECT sensor. Replace as necessary.
  3. Check Power Supply (Low Speed) Turn ignition off. Disconnect cooling fan relay No. 1. Using voltmeter, measure voltage between ground and cooling fan relay No. 1 harness connector terminals No. 1 (White/Blue wire), No. 3 (Green wire), No. 6 (Green/White wire). If battery voltage is present, go to next step. If battery voltage is not present, check for blown fuses "C" (40-amp), "B" (40-amp) and No. 36 (10-amp) in fuse junction box. Check harness for open or short between cooling fan relay No. 1 and fuse terminals. Repair open circuit, short to ground or short to power in harness or connectors.
  4. Check Ground Circuit (Low Speed) Turn ignition off. Disconnect cooling fan motors No. 1 and 2 harness connectors. (Scheme 4) Check for continuity between cooling fan motor No. 1 terminal (L+) and cooling fan relay No. 1 terminal No. 5 (Green/Black wire). Repeat check between cooling fan motor No. 2 terminal (L+) and cooling fan relay No. 1 terminal No. 7 (Green/Red wire). If continuity exists, check harness for short to ground and short to power. Check harness for continuity between cooling fan motors No. 1 and No. 2 terminals (L-) and body ground. If continuity exists, check harness for short to ground and short to power. Go to next step. If continuity is not present, repair harness or connectors.
  5. Check Output Signal Circuit (Low Speed) Disconnect ECM harness connector. Check for continuity between ECM harness connector terminal No. 14 and cooling fan relay No. 1 harness connector terminal No. 2 (Light Green/Red wire). If continuity does not exist, check harness and connectors between ECM and relay No. 1. See «WIRING DIAGRAMS»(ref-8703-S34361767142000091400000). Check harness for open or short between cooling fan relay No. 1 and ECM. Repair open or short to power in Light Green/Red wire. If continuity exists, go to next step.
  6. Check Cooling Fan Relay No. 1 (Low Speed) Disconnect cooling fan relay No. 1. Apply 12 volts and ground between relay terminals No. 1 and 2. (Scheme 5) Using an ohmmeter, check for continuity between terminals No. 3 and 5 and between terminals No. 6 and 7. If continuity does not exist, replace fan relay No. 1. If continuity exists, go to step 11.
  7. Check Power Supply (High Speed) Turn ignition off. Disconnect cooling fan relays No. 2 and 3. (Scheme 3) Turn ignition on. Using voltmeter, measure voltage between ground and fan relay No. 2 terminals No. 1 (Brown wire) and No. 3 (Green wire). Repeat procedure for fan relay No. 3 terminals No. 1 (Brown wire) and No. 3 (Green/White wire). (Scheme 5) If battery voltage is present, go to next step. If battery voltage is not present, check for blown fuse No. 36 (10-amp), fuse "B" (40-amp) and fuse "C" (10-amp). Repair open circuit, short to ground, or short to power in harness or connectors.
  8. Check Ground Circuits (High Speed) Turn ignition off. Disconnect cooling fan motors No. 1 and 2 harness connectors. (Scheme 4) Using an ohmmeter, check for continuity between cooling fan relay No. 2 terminal No. 5 (Green/Yellow wire) and cooling fan relay motor No. 1 terminal (H+). Repeat procedure for cooling fan motor No. 2 terminal (H+) and cooling fan relay No. 3 terminal No. 5 (Green/Orange wire). If continuity exists, check harness for short to ground or short to power. Check for continuity between fan motor No. 1 harness connector terminal (H-) and fan relay No. 2 terminals No. 6 (Light Green/Blue wire) and No. 7 (Blue wire) and ground. Repeat procedure for fan motor No. 2 terminal (H-) and fan relay No. 3 terminals No. 6 (Light Green/Red wire) and No. 7 (Blue wire). (Scheme 5) If continuity exists, go to next step. If continuity does not exist, repair harness or connectors.
  9. Check Output Signal (High Speed) Disconnect ECM harness connector. Check for continuity between ECM terminals No. 13 and terminal No. 2 of cooling fan relays No. 2 and 3. If continuity exists, check harness for short to ground and short to power. Go to next step. If continuity does not exist, check harness and connectors between ECM and cooling fan relays. Check harness for open or short between cooling fan relays No. 2 and 3 and ECM. Repair open circuit, short to ground or short to power in harness or connectors.
  10. Check Cooling Fan Relays No. 2 & 3 (High Speed) Disconnect cooling fan relays No. 2 and 3. Apply 12 volts and ground between relay terminals No. 1 and 2. (Scheme 5) Using an ohmmeter, check for continuity between terminals No. 3 and 5 and between terminals No. 6 and 7. If continuity does not exist, replace fan relay(s). If continuity exists, go to next step.
  11. Check Cooling Fan Motors (Low & High Speed) Disconnect cooling fan motor harness connectors. Connect 12 volts and ground to terminals L+ and L-. Low speed fan should operate. Connect two 12-volt jumpers to terminals L+ and H+, and ground to terminals L- and and H-. High speed fan should operate. If fan motors do not operate as specified, replace motor(s).

Scheme 3

Scheme 3
Scheme 3

Scheme 4

Scheme 4
Scheme 4

Scheme 5

Scheme 5
Scheme 5

1999

  1. Check Low Speed Fan Operation Disconnect cooling fan relays No. 2 and 3, located in engine compartment, near battery. Start engine. Set temperature lever to full cold position. Turn A/C switch and blower switch on. Run engine at idle for several minutes. Verify cooling fan operates at low speed. If fan does not operate at low speed, go to step 5 . If fan operates at low speed, go to next step.
  2. Check High Speed Fan Operation Turn ignition off. Reconnect cooling fan relays No. 2 and 3. Turn A/C switch and blower fan switch off. Disconnect Engine Coolant Temperature (ECT) sensor harness connector. Connect a 150-ohm resistor across ECT sensor harness connector terminals. Start engine. Verify cooling fan operates at high speed. If fan does not operate at high speed, go to step 9 . If fan operates at high speed, go to next step.
  3. Check Harness Continuity Between Cooling Fan Relays No. 2 & 3 & Ground Turn ignition off. Disconnect cooling fan relays No. 2 and 3. Disconnect triple-pressure switch harness connector. Check both relays and triple-pressure switch for continuity between terminals No. 2 and 3, and between terminal No. 2 and ground. If continuity exists, check harness for short to ground and short to power. Go to next step. If continuity does not exist, check joint connector No. 3 E11. Check harness for open or short between cooling fan relays No. 2 and 3 and triple-pressure switch. Check harness for open or short between triple-pressure switch and ground. Repair open circuit, short to ground, or short to power in harness connectors.
  4. Check Triple-Pressure Switch Check triple-pressure switch operation. See appropriate article in AIR CONDITIONING & HEATING. Replace triple-pressure switch, if necessary. If switch operates, check cooling system for leaks, check radiator cap pressure and thermostat operation. Repair as necessary. Inspect ECT sensor. Replace as necessary.
  5. Check Power Supply (Low Speed) Turn ignition off. Disconnect cooling fan relay No. 1. Turn ignition on. Using voltmeter, measure voltage between cooling fan relay No. 1 harness connector terminals No. 1 (Green/Yellow wire) and ground and No. 3 (White/Blue wire) and ground. If battery voltage is not present, check for blown fuse No. 17 (10-amp) or fault in Green/Yellow wire. See «WIRING DIAGRAMS»(ref-8703-S34361767142000091400000) . Check for burnt fusible link "D" (30-amp) or fault in White/Blue wire. Check harness for open or short between cooling fan relay No. 1 and battery. Repair or replace as necessary. If battery voltage is present, go to next step.
  6. Check Ground Circuit (Low Speed) Turn ignition off. Disconnect cooling fan motors No. 1 and 2 harness connectors. Using an ohmmeter, check for continuity between terminals No. 5 of cooling fan relay No. 1 and terminal No. 1 (White/Black wire) of cooling fan motors. If continuity exists, check harness for short. Check for continuity between motor terminal No. 4 (Black wire) and ground. If continuity exists, check harness for short to ground and short to power. Go to next step. If continuity does not exist, check joint connector No. Check harness for open or short between cooling fan relay No. 1 and cooling fan motors. Repair open , short to ground or short to power in harness connectors.
  7. Check Output Signal Circuit (Low Speed) Disconnect ECM harness connector. Using an ohmmeter, check for continuity between ECM harness connector terminal No. 14 and cooling fan relay No. 1 harness connector terminal No. 2 (Light Green/Red wire). If continuity exists, check harness for short to ground. Go to next step. If continuity does not exist, check harness for open or short between cooling fan relay No. 1 and ECM. Repair open, short to ground, or short to power in harness connectors.
  8. Check Cooling Fan Relay No. 1 (Low Speed) Disconnect cooling fan relay No. 1. Apply 12 volts and ground between terminals No. 1 and 2. Continuity should exist between terminals No. 3 and 5. Disconnect power supply. Continuity should not exist between terminals No. 3 and 5. If continuity is as specified, go to step 14 . If continuity is not as specified, replace relay.
  9. Check Power Supply (High Speed) Turn ignition off. Disconnect cooling fan relays No. 2 and 3. Turn ignition on. Using voltmeter, measure voltage of each relay between terminal No. 1 (Green/Yellow wire) and ground and between terminal No. 3 (White/Green wire) and ground. If battery voltage is not present, check for faulty joint connector No. 2. Check fusible links "D" (30-amp) and "E" (30-amp). Check harness for open or short between cooling fan relays No. 2 and 3 and fuse No. 17. Check harness for open or short between cooling fan relays No. 2 and 3 and battery. Repair or replace as necessary. If battery voltage is present, go to next step.
  10. Check Ground Circuit (High Speed - Fan Motor No. 1) Turn ignition off. Disconnect cooling fan motor No. 1 and 2 harness connectors. Check for continuity between fan motor No. 1 harness connector terminals No. 2 and fan relay No. 2 harness connector terminal No. 5 (White/Blue wire). Check for continuity between fan motor No. 1 harness connector terminal No. 3 and fan relay No. 2 harness connector terminal No. 6 (White/Red wire). Check for continuity between fan relay No. 2 harness connector terminal No. 7 (Black wire) and ground. If continuity exists, check harness for short. Go to next step. If continuity does not exist, repair open, short to ground, or short to power in harness connectors.
  11. Check Ground Circuit (High Speed - Fan Motor No. 2) Check for continuity between fan motor No. 2 harness connector terminal No. 2 and fan relay No. 3 harness connector terminal No. 5 (White/Blue wire). Check for continuity between fan motor No. 2 harness connector terminal No. 3 and fan relay No. 3 harness connector terminal No. 6 (White/Red wire). Check for continuity between fan relay No. 3 harness connector terminal No. 7 (Black wire) and ground. If continuity exists, check harness for short to ground and short to power. Go to next step. If continuity does not exist, repair open circuit, short to ground, or short to power in harness connectors.
  12. Check Output Signal Circuit (High Speed) Disconnect ECM harness connector. Using an ohmmeter, check for continuity between ECM harness connector terminal No. 13 and fan relays No. 2 and 3 harness connector terminals No. 2 (Light Green wire). If continuity does not exist, check harness connectors and joint connector No. 3. Check harness for open or short between cooling fan relays No. 2 and 3 and ECM. Repair open short/ground or short/power in Light Green wire. If continuity exists, check harness for short to ground and short to power. Go to next step.
  13. Check Cooling Fan Relays No. 2 & 3 (High Speed) Disconnect cooling fan relays No. 2 and 3. Apply 12 volts between terminals No. 1 and 2. Continuity should exist between terminals No. 3 and 5, and between terminals No. 6 and 7. Disconnect power supply. Continuity should not exist between terminals No. 3 and 5, or terminals No. 6 and 7. If continuity is as specified, go to next step. If continuity is not as specified, replace relay(s).
  14. Check Cooling Fan Motors (Low & High Speed) Disconnect cooling fan motor connectors. Apply 12 volts to motor connector terminal No. 1 (White/Black wire) and ground terminal No. 4 (Black wire). Motor should operate at low speed. Using 2 jumpers, apply power to terminals No. 1 (White/Black wire) and No. 2 (White/Blue wire), and ground terminals No. 3 (White/Red wire) and No. 4 (Black wire). Motor should operate at high speed. If motor operates as specified, problem may be intermittent. If motor does not operate as specified, replace motor(s).

Scheme 6

Scheme 6: COOLING FAN CONTROL TEST (QUEST)
Scheme 6: COOLING FAN CONTROL TEST (QUEST)

Scheme 7

Scheme 7
Scheme 7
  1. Check Low Speed Fan Operation Ensure coolant level is okay. Turn ignition off. Disconnect cooling fan relays No. 2 and 3. (Scheme 6) Start engine. Set A/C temperature control lever to full cold position. Turn A/C switch and blower fan switch on. Run engine at idle for several minutes. Cooling fan should operate at low speed. If cooling fan operates, go to next step. If cooling fan does not operate, go to step 3.
  2. Check High Speed Fan Operation Turn ignition off. Reconnect cooling fan relays No. 2 and 3. Disconnect cooling fan relay No. 1. (Scheme 6) Turn ignition on. Turn A/C switch and blower fan switch off. Disconnect Engine Coolant Temperature (ECT) sensor harness connector. Connect a 150-ohm resistor across ECT sensor harness connector terminals. Start engine. Cooling fan should operate at high speed. If cooling fan does not operate at high speed, go to step 7. If cooling fan operates at high speed, check cooling system for leaks, check radiator cap pressure and thermostat operation. Replace or repair as necessary. Check ECT sensor. Replace as necessary.
  3. Check Power Supply (Low Speed) Turn ignition off. Disconnect cooling fan relay No. 1. Turn ignition on. Measure voltage between cooling fan relay No. 1 harness connector terminals No. 1 (Blue wire) and ground, and terminal No. 5 (White/Blue wire) and ground. (Scheme 7) If battery voltage is present, go to next step. If battery voltage is not present, check fuse No. 29 (10-amp) and fusible link (75-amp). If fuse and fusible link are okay, check open in circuit between fuse block and relay. See «WIRING DIAGRAMS»(ref-8703-S34361767142000091400000).
  4. Check Ground Circuit (Low Speed) Turn ignition off. Disconnect cooling fan motor harness connector. Using ohmmeter, check for continuity between fan motor harness connector terminal No. 2 and fan relay No. 1 harness connector terminal No. 3 (Blue/White wire). If continuity does not exist, repair open in Blue/White wire. If continuity exists, check for continuity between fan motor harness connector terminal No. 3 (Black wire) and ground. If continuity exists, go to next step. If continuity does not exist, repair open or short in Black wire.
  5. Check Output Signal Circuit (Low Speed) Disconnect ECM harness connector. Check for continuity between ECM harness connector terminal No. 38 and fan relay No. 1 connector terminal No. 2 (Blue/Orange wire). If continuity does not exist, check repair open in Blue/Orange wire. If continuity exists, go to next step.
  6. Checking Cooling Fan Relay (Low Speed) Remove cooling fan relay No. 1. Apply 12 volts and ground to relay terminals No. 1 and 2. (Scheme 7) Check for continuity between relay terminals No. 3 and 5. If continuity does not exist, replace relay. If continuity exists, go to step 11.
  7. Check Power Supply (High Speed) Turn ignition off. Disconnect cooling fan relays No. 2 and 3. (Scheme 6) Turn ignition on. Measure voltage between cooling fan relay No. 2 harness connector terminal No. 1 (Blue wire) and ground, and between terminal No. 5 (color N/A) and ground. Repeat procedure for cooling fan relay No. 3. If battery voltage is present, go to next step. If battery voltage is not present, check fuse No. 29 (10-amp) and fusible link (75-amp). If okay, repair open in harness between fuse block and relay. See «WIRING DIAGRAMS»(ref-8703-S34361767142000091400000).
  8. Check Power & Ground Circuits (High Speed) Turn ignition off. Disconnect cooling fan motor harness connector. Check for continuity in Blue/Red wire between fan motor harness connector terminal No. 1 and fan relay No. 2 harness connector terminal No. 3. Repeat procedure for cooling fan relay No. 3. If continuity is present, go to next step. If continuity is not present, repair open in Blue/Red wire between cooling fan and cooling fan relays No. 2 and 3. Also check for short to ground and short to power. Repair short to ground or short to power in harness or connectors, if necessary.
  9. Check Output Signal Circuit (High Speed) Disconnect ECM harness connector. Check for continuity between ECM harness connector terminal No. 36 and cooling fan relay No. 2 harness connector terminal No. 2 (Brown/White wire). Repeat procedure for cooling fan relay No. 3. Also check harness for short to ground and short to power. Check harness connectors. If continuity does not exist, repair open or short in Brown/White wire. See «WIRING DIAGRAMS»(ref-8703-S34361767142000091400000). If continuity exists, go to next step.
  10. Check Cooling Fan Relays No. 2 & 3 (High Speed) Disconnect and inspect cooling fan relays No. 2 and 3. Connect battery voltage to relay terminals No. 1 and 2. (Scheme 7) Using an ohmmeter, check for continuity between relay terminals No. 3 and 5. If continuity does not exist, replace relay. If continuity exists, go to next step.
  11. Test Cooling Fan Motor (Low & High Speed) Disconnect cooling fan motor harness connectors. Connect positive battery voltage to fan motor terminal No. 2 and ground to fan motor terminal No. 3. Fan motor should operate at low speed. Connect battery positive to fan motor terminal No. 1 and negative lead to fan motor terminal No. 3. Fan motor should operate at high speed. If fan motor does not operate as described, replace fan motor. If fan motor is okay, check ECM pin terminals and/or wiring harness connectors for corrosion and damage. Repair or replace as necessary.

COOLING FAN CIRCUIT (SENTRA)

Note. On models equipped with M/T, cooling fan(s) operates at high speed only. M/T models equipped with A/C use 2 cooling fans. On 2000 Sentra models, electric cooling fans are monitored and controlled by self-diagnostic system. Malfunctions in electric cooling fan circuit should set a related trouble code (coolant overtemp). For specific testing procedures related to 2000 Sentra, see appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.

1999 1.6L & 2.0L

  1. Check Cooling Fan (Low Speed A/T & M/T) Operation On A/T models, disconnect cooling fan relays No. 2 and 3. (Scheme 8) On all models, start engine. Place temperature control lever at full COLD position. Turn A/C switch and blower fan switch on. Run engine at idle for a few minutes with air conditioner operating. Ensure cooling fans operate at low speed for A/T models and at high speed for M/T models. If fans operate at specified speed, go to next step. If fans do not operate as specified, go to step 3.
  2. Checking Cooling Fan (High Speed A/T) Operation Turn ignition off. Reconnect cooling fan relays No. 2 and 3. Disconnect cooling fan relay No. 1. Turn ignition on. Turn A/C switch and blower fan switch off. Disconnect engine coolant temperature sensor harness connector. Connect a 150-ohm resistor to engine coolant temperature sensor connector. Start engine. Verify cooling fan operates at high speed. If fan does not operate at high speed, go to step 7. If fan operates at high speed, check cooling system for leaks, check radiator cap pressure and thermostat operation. Repair as necessary. Inspect ECT sensor. Replace as necessary.
  3. Check Power Supply (Low Speed A/T & M/T) Turn ignition off. Disconnect cooling fan relay No. 1. Turn ignition on. Using a voltmeter, measure voltage between cooling fan relay No. 1 harness connector terminal No. 1 (Brown wire) and ground. Check voltage between cooling fan relay No. 1 harness connector terminal No. 3 (Green wire) and ground. If battery voltage is not present, check for blown fuse No. 25 (10-amp) or fault in Brown wire. Repair or replace as required. Check for burnt fusible link "E" (30-amp) or fault in Green wire. Check harness for open or short between cooling fan relay No. 1 and battery. Repair open circuit, short to ground or short to power in harness or connectors. If battery voltage is present, go to next step.
  4. Check Ground Circuit (Low Speed A/T & M/T) Turn ignition off. Disconnect cooling fan motors No. 1 and 2 harness connectors. Using an ohmmeter, check for continuity between fan motor No. 1 harness connector terminal No. 1 and fan relay No. 1 harness connector terminal No. 5 (Green/Black wire). If continuity exists, check harness for short. Check for continuity between fan motor connector terminals No. 4 (A/T models) or No. 2 (M/T models) and ground. If continuity exists, check harness for short to ground and short to power. Go to next step. If continuity does not exist, repair harness or connectors.
  5. Check Output Signal Circuit (Low Speed A/T & M/T) Disconnect ECM harness connector. Check for continuity between ECM harness connector terminal No. 14 and cooling fan relay No. 1 harness connector terminal No. 2 (Light Green/Red wire). If continuity does not exist, check harness for open or short between cooling ran relay No. 1 and ECM harness connector. Repair open circuit, short to ground, or short to power in harness or connectors. If continuity exists, go to next step.
  6. Check Cooling Fan Relays (Low Speed A/T & M/T) Disconnect suspect cooling fan relay. Apply battery power to terminal No. 1 and ground terminal No. 2. (Scheme 7) Check for continuity between terminals No. 3 and 5. If continuity exists, go to step 11. If continuity does not exist, replace relay(s).
  7. Check Power Supply (High Speed - A/T) Turn ignition off. Disconnect cooling fan relays No. 2 and 3. Turn ignition on. Using voltmeter, measure voltage between cooling fan relay No. 2 terminal No. 1 (Brown wire) and ground, and between terminal No. 3 (Green wire) and ground. Repeat procedure for cooling fan relay No. 3. Battery voltage should exist. If battery voltage is present, go to next step. If battery voltage does not exist, check for blown fuse No. 25 (10-amp) or fault in Brown wire. Check for burnt fusible link "E" (30-amp) or fault in Green wire. Check harness for open or short between cooling fan relays No. 2 and 3 and fuse. Check harness for open or short between cooling fan relays No. 2 and 3 and battery. Repair harness or connectors as needed.
  8. Check Power & Ground Circuit (High Speed - A/T) Turn ignition switch off. Disconnect cooling fan motor No. 1 and 2 harness connectors. Using ohmmeter, check for continuity between cooling fan relay No. 2 terminal No. 5 and cooling fan motors No. 1 and 2 terminal No. 2. If continuity exists, check harness for short. Check harness continuity between cooling fan relay No. 3 terminal No. 3 and cooling fan motors No. 1 and 2 terminal No. 3. Check for harness continuity between cooling fan relay No. 3 terminal No. 5 and ground. If continuity exists, check harness for short to ground and short to power. Go to next step. If continuity does not exist, repair harness or connectors
  9. Check Output Signal Circuit (High Speed - A/T) Disconnect ECM harness connector. Using ohmmeter, check for continuity between ECM harness connector terminal No. 13 and cooling fan relay No. 3 terminal No. 2. Check for continuity between ECM harness connector terminal No. 14 and cooling fan relay No. 2 terminal No. 2. If continuity exists, check harness for short to ground and short to power. Go to next step. If continuity does not exist, check harness for open or short between cooling fan relays No. 2 and 3 and ECM. Repair open circuit, short to ground or short to power in harness or connectors.
  10. Check Cooling Fan Relays (High Speed - A/T) Disconnect suspect cooling fan relay. Apply battery power to terminal No. 1, and ground terminal No. 2. (Scheme 7) Check for continuity between terminals No. 3 and 5. If continuity exists, go to next step. If continuity does not exist, replace relay(s).
  11. Check Cooling Fan Motors(Low Speed & High Speed) Disconnect cooling fan motor connectors No. 1 and 2. On A/T models, check for low and high speed. To check for low speed, apply battery voltage to cooling fan motor No. 1 terminal No. 1, and ground terminal No. 4. To check for high speed, apply battery voltage to terminal No. 2, and ground terminal No. 3. On M/T models, check for high speed. Apply battery voltage to terminal No. 1, and ground terminal No. 2. Repeat procedure for cooling fan motor No. 2. If cooling fan motors operate correctly, problem is intermittent. Go to next step. If cooling fan motor(s) do not operate, replace motor(s).

Scheme 8

Scheme 8
Scheme 8

Electric Cooling Fan System Wiring Diagram (1999-2000 Altima). Scheme 9

Scheme 9: Electric Cooling Fan System Wiring Diagram (1999-2000 Altima)
Scheme 9: Electric Cooling Fan System Wiring Diagram (1999-2000 Altima)

Electric Cooling Fan System Wiring Diagram (1999-2000 Frontier 3.3L & 2000 Xterra). Scheme 10

Scheme 10: Electric Cooling Fan System Wiring Diagram (1999-2000 Frontier 3.3L & 2000 Xterra)
Scheme 10: Electric Cooling Fan System Wiring Diagram (1999-2000 Frontier 3.3L & 2000 Xterra)

Electric Cooling Fan System Wiring Diagram (1999 Maxima). Scheme 11

Scheme 11: Electric Cooling Fan System Wiring Diagram (1999 Maxima)
Scheme 11: Electric Cooling Fan System Wiring Diagram (1999 Maxima)

Electric Cooling Fan System Wiring Diagram (2000 Maxima). Scheme 12

Scheme 12: Electric Cooling Fan System Wiring Diagram (2000 Maxima)
Scheme 12: Electric Cooling Fan System Wiring Diagram (2000 Maxima)

Electric Cooling Fan System Wiring Diagram (1999-2000 Quest). Scheme 13

Scheme 13: Electric Cooling Fan System Wiring Diagram (1999-2000 Quest)
Scheme 13: Electric Cooling Fan System Wiring Diagram (1999-2000 Quest)

Electric Cooling Fan System Wiring Diagram (1999 Sentra). Scheme 14

Scheme 14: Electric Cooling Fan System Wiring Diagram (1999 Sentra)
Scheme 14: Electric Cooling Fan System Wiring Diagram (1999 Sentra)

Electric Cooling Fan System Wiring Diagram (2000 Sentra). Scheme 15

Scheme 15: Electric Cooling Fan System Wiring Diagram (2000 Sentra)
Scheme 15: Electric Cooling Fan System Wiring Diagram (2000 Sentra)

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