Power Circuit Check
- Disconnect ECU connector. Turn ignition on. Check for battery voltage on harness side terminal No. 1. See Fig 1
. If voltage is not present, check for blown 10-amp power fuse between ignition switch and ECU.
Courtesy of NISSAN MOTOR CO., U.S.A.
- If fuse is blown, check for short to ground in White/Green wire between fuse and control unit. If fuse is not blown, check for open in White/Green wire between fuse and control unit.
- Start engine. Check for voltage on ECU connector harness side terminal No. 15. See Fig 1
. If voltage is not present, go to next step. If voltage is greater than 6 volts, power circuits are okay. Check ECU ground circuit.
- Check for open in Yellow/Red wire between ECU terminal No. 15 and alternator terminal "L". If wire is okay, check voltage at terminal "L" of alternator. If voltage is still not present, repair or replace alternator.