Cooling Fan Low Speed Circuit
WARNING: This page is about a different car, the 2002 Nissan Sentra. However, it is still accessible from the selected car via links, so may be relevant.
- Check Cooling Fan Power Supply Circuit
Turn ignition off. Reconnect all harness connectors. Remove cooling fan relay No. 1. See Figure . Turn ignition on. Measure voltage between ground and cooling fan relay No. 1 harness connector terminals No. 1, 3 and 6. See Fig 1 . If battery voltage exists at all terminals, go to step 3 . If battery voltage does not exist at all terminals, go to next step. - Detect Malfunctioning Part
Check the following:- Fuse and fusible link box connectors E23 and E25.
- Fuse block connector E103.
- Fuse No. 20 (10-amp)
- Fusible links "h" and "i" (both 40-amp).
- Harness for open or short between cooling fan relay No. 1 and fuse.
- Harness for open or short between cooling fan relay No. 1 and battery.
Repair as necessary. Perform DTC CONFIRMATION TEST (OVERALL FUNCTION CHECK) to verify repair.
- Check Cooling Fan Ground Circuit For Open & Short
Turn ignition off. Disconnect both cooling fan motor harness connectors. See Fig 2 . Check the following:- Check continuity between cooling fan relay No. 1 harness connector terminal No. 5 and cooling fan motor No. 1 harness connector terminal No. 1.
- Check continuity between body ground and cooling fan motor No. 1 harness connector terminal No. 4.
- Check continuity between cooling fan relay No. 1 harness connector terminal No. 7 and cooling fan motor No. 2 harness connector terminal No. 2.
- Check continuity between body ground and cooling fan motor No. 2 harness connector terminal No. 2.
Continuity should exist. Also, check harness for short to ground and short to power. If problem is found, repair as necessary. Perform DTC CONFIRMATION TEST (OVERALL FUNCTION CHECK) to verify repair. If problem is not found, go to next step.
- Check Cooling Fan Output Signal Circuit For Open & Short
Disconnect ECM harness connector. See Figure . Check continuity between cooling fan relay No. 1 harness connector terminal No. 2 and ECM harness connector terminal No. 13. Continuity should exist. Also, check harness for short to ground and short to power. If problem is found, go to next step. If problem is not found, go to step 6 . - Detect Malfunctioning Part
Check the following:- Harness connectors E10 and F48.
- Harness for open or short between cooling fan relay No. 1 and ECM.
Repair as necessary. Perform DTC CONFIRMATION TEST (OVERALL FUNCTION CHECK) to verify repair.
- Check Cooling Fan Relay No. 1
Check cooling fan relay No. 1 as shown in illustration. See Fig 3 . If cooling fan relay No. 1 is okay, go to next step. If cooling fan relay No. 1 is not okay, replace cooling fan relay No. 1. Perform DTC CONFIRMATION TEST (OVERALL FUNCTION CHECK) to verify repair. - Check Cooling Fan Motors No. 1 & 2
Check cooling fan motors as shown in illustrations. See Fig 4 and Fig 5 . If cooling fan motors are okay, go to next step. If cooling fan motors are not okay, replace inoperative cooling fan motor. Perform DTC CONFIRMATION TEST (OVERALL FUNCTION CHECK) to verify repair. - Check For Intermittent
Check for intermittent condition. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article. Perform DTC CONFIRMATION TEST (OVERALL FUNCTION CHECK) to verify repair.