No power to fuel pump and coil pack fuses on 2.5 efi outboard

markf1962

Recruit
Joined
Oct 2, 2017
Messages
4
Suddenly lost power to 2of4 fuses on my mers.checked every ground and connection,changed ECM,key switch,and pick up for crank I have power on my purple ignition wire and going into relays but not opening relays. Any thoughts?
 

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
42,466
Merc uses a main power relay (MPR) to power up the others. The MPR is energized by a ground being applied from the ECM. Not knowing which 2.5 you have the pic is an example. The MPR and fuel pump relays get power when key is turned ON. Unless the MPR sees a ground from the ECM nothing else gets power

555 relays.jpg
 

markf1962

Recruit
Joined
Oct 2, 2017
Messages
4
Thank you,I have looked all over for a vin# with no luck I know it's a 2004 an I'm pretty sure it's an optimax but I'm sure it's a pain in my butt.il see if I can locate a main breaker thanks again
 

markf1962

Recruit
Joined
Oct 2, 2017
Messages
4
Pics,maybe someone knows the model?
 

Attachments

  • 20240702_183333.jpg
    20240702_183333.jpg
    2.4 MB · Views: 4
  • 20250214_143310.jpg
    20250214_143310.jpg
    1.4 MB · Views: 4

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
42,466
Need to scan the motor for codes
Do have a manual showing 2.5/3.0 for 2002 and newer V6

Shows 2 places to look for +5V reference

Slide1.JPGSlide2.JPG
 
Top