Mercury MerCruiser MCM 7.4L MPI - Page 682

GENERAL SYSTEM DIAGNOSTICS
SERVICE MANUAL NUMBER 23
90-861326--1 MARCH 1999 Page 5E-89
Chart A-7 (6 of 6): Ignition System Check
Step Action Value(s) Yes No
18
Replace faulty pick-up coil.
Is Action Complete?
–
Go to OBD
System
Check
–
19
Inspect distributor cap for water,
cracks, etc. If OK, replace faulty
distributor rotor.
Is Action Complete?
–
Go to OBD
System
Check
–
20
Check for open or short to
ground in CKT 3, the pink wire
from the ignition module “+”
terminal to the ignition coil. Also
check for open CKT 902, the red
wire from the EFI system relay to
the ignition coil.
Is Action Complete?
–
Go to OBD
System
Check
–
21
Check for open or short to
ground in CKT 121, the brown
wire from the ignition module “C”
terminal to the ignition coil. If OK,
replace faulty ignition coil.
Is Action Complete?
–
Go to OBD
System
Check
–
22
Repair faulty connections or
open tach lead.
Repeat Step 8.
–
Go to OBD
System
Check
–
23
Check ignition module ground. If
OK, replace faulty ignition
module.
Is Action Complete?
–
Go to OBD
System
Check
–
24
Replace distributor pole piece
and shaft assembly.
Is Action Complete?
–
Go to OBD
System
Check
–
25
A mechanical repair will be
necessary before continuing with
this test.
– – –
Downloaded from https://needmanual.com/!
Index