Mercury MerCruiser MIE 7.4L MPI User Manual

GENERAL SYSTEM DIAGNOSTICS SERVICE MANUAL NUMBER 23
Page 5E-64 90-861326--1 MARCH 1999
Chart A-2 (3 of 3): Malfunction Indicator Lamp “On” Steady - No DLC Data or
Will Not Flash DTC 12 - Marine Diagnostic Trouble Code (MDTC) Tool Installed
Step Action Value(s) Yes No
1
Was the “On-Board Diagnostic”
(OBD)
System Check Performed?
-
Go to Step 2
Go to OBD
System Check
2
1. Ignition “ON,” engine “OFF.”
2. Switch MDTC tool to “Service
Mode.”
Does The MIL Flash DTC 12?
-
Go to Step 6 Go to Step 3
3
1. Ignition “OFF,” disconnect
ECM connectors.
2. Ignition “ON,” engine “OFF,”
observe the MIL.
Is The MIL “ON”?
-
Go to Step 7 Go to Step 4
4
1. Ignition “OFF.”
2. With ECM “J1” connector dis-
connected, jump terminals “A”
to “B” at the DLC.
3. Connect test light between
ECM connector terminal “J1-7”
and battery positive (B+).
Does Test Light Illuminate
Brightly?
-
Go to Step 5 Go to Step 8
5
1. Verify correct operation of
MDTC tool on a known good
system.
2. If a problem is found, repair as
necessary.
Is Action Complete?
_
Go to OBD
System Check
Go to Step 9
6
1. If problem was no DLC data
(using scan tool), check
serial data CKT 461 for an
open or short to ground.
2. If a problem is found, repair as
necessary.
Is Action Complete?
-
Go to OBD
System Check
Go to Step 9
7
Locate and repair short to ground
in CKT 419.
Is Action Complete?
-
Go to OBD
System Check
_
8
Locate and repair open in CKT 450
and/or CKT 451.
Is Action Complete?
-
Go to OBD
System Check
_
9
1. Repair faulty ECM connections
or replace faulty ECM.
2. Recheck for DTC 12.
Is Action Complete?
_
Go to OBD
System Check
_
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Index

Mercury MerCruiser MIE 7.4L MPI Specifications

General

Brand	Mercury
Model	MerCruiser MIE 7.4L MPI
Category	Engine
Language	English