ECM POWER PROBLEM

2005 NISSAN PATHFINDER
170,000 MILES • 4.0L • 4WD • AUTOMATIC
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DALELEE2
  • MEMBER
  • 1 POST
My truck has lost ability to rush. Have no communication to ALDL connector, no check engine light. Will crank over, no security light. Drive select indicator comes on for about 1 second showing 4 wheel drive, then goes off. When moving 4 wheel drive switch can hear transfer case motor running. Testing has determined most or all 5 volt supply voltages gone. I'm at the point I need to check power and ground inputs to ECM. Difficult process. Is there a trick to removing plastic cover from ECM connectors so I can check for power and grounds at ECM?
Jul 20, 2026 at 5:06 PM
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STRAILER
  • ASE Certified Mechanic
  • 54,832 POSTS
  • ASE Certified Mechanic
Yep, I would check the fuses first,
Jul 20, 2026 at 6:57 PM
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STRAILER
  • ASE Certified Mechanic
  • 54,832 POSTS
  • ASE Certified Mechanic
Here are the fuses I would check and there locations. Also, check the main engine wiring harness grounds to the engine. Also, try swapping out he main PCM power relay. Let me know how it goes.
Jul 20, 2026 at 7:00 PM
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