• Global announcements
No global announcements

  • Latest Posts

1999 Dual 454 with Mefi 3 ECM - Master/Slave relationship


Hello all, in my checking of actual engine hours using my Rinda software vs the Helm Hour analog gauges that are not 100% accurate. I noticed that both engines come up as "Master" and NOT as ("Master"/"Slave") on the bottom left of the screen when communicating with the engine. Is this an issue or a non-issue? Any guidance would be greatly appreciated.

Information of Vessel:
1999 Carver 406
Engine Starboard Mercruiser 7.4L MPI MIE V-8 gasoline naturally aspirated engine - 330hp SN- 0L303931
Engine Port Mercruiser 7.4L MPI MIE V-8 gasoline naturally aspirated engine - 330hp SN- 0L303934

MEFI 3 ECM on each Engine

I found this text in a publication named
"MerCruiser EFI Engine History and Major Changes"
"The engine control module (ECM) on all 1996 and newer model year EFI engines has the
“Power Reduction Mode” disabled. Because of this change, it is important that 1995 (and
older) models not be intermixed with 1996 (and newer) models on multiple engine boats. It
is important that all of the engines in a boat have either the power reduction mode enabled
or disabled, but not a combination of both.
The 3-pin Master/Slave connector and the 2-pin Safety Lanyard Stop Circuit connector have
been removed on some 1996 and newer MEFI 1 models and all MEFI 2 and MEFI 3 models.

On these newer models, if the Master/Slave functions are desired, it is necessary to build a
custom data link harness and connect it between the DLC connectors on the engines. The
serial data terminal (Pin G, orange [or orange/black] lead) on the data link connector
(DLC) of both engines must be connected together and the master/slave terminal (Pin
H, yellow lead) on the Slave engine’s DLC must be grounded.
"

I read this as Master / Master is OK

Views: 3016  •  Comments: 3  •  Write comments [ Back ]



  • Who is online?
  • In total there are 1073 users online :: 7 registered, 0 hidden and 1066 guests


  • Newest members


  • Statistics
  • Totals
    Total posts 68179
    Total topics 8193
    Total Announcements: 0
    Total Stickies: 4
    Total Attachments: 6673

    Topics per day: 2
    Posts per day: 14
    Users per day: 2
    Topics per user: 1
    Posts per user: 6
    Posts per topic: 8

    Total members 11568
    Our newest member Kwat21

  •  Birthdays
  • No birthdays today
    In the next 30 days
    No members have a birthday within this period of time.

  • Sponsors