Ignition System Check
(1 of 2)
IGNITION CONTROL
DIST. REFERENCE “HIGH”
BYPASS
DIST. REFERENCE “LOW”
TO TACH
TO DISTRIBUTOR
TEST DESCRIPTION:
4. Checks for a shorted module or grounded circuit
from the ignition coil to the module. The distribu-
tor module should be turned OFF, so normal volt-
age should be about 12 volts.
Number(s) below refer to circled number(s) on the
diagnostic chart.
1.
Two spark plug wires are checked, to ensure that
an open is not present in a spark plug wire.
If the module is turned ON, the voltage would be
low, but above 1 volt. This could cause the igni-
tion coil to fail from excessive heat.
If spark occurs with Ignition Control (IC) connec-
tor disconnected, magnetic field output is too low
for Ignition Control (IC) operation.
With an open ignition coil primary winding, a
small amount of voltage will leak through the
module from the Battery Positive (B+) to the
“Tach” terminal.
2.
3.
A spark indicates the problem must be the distrib-
utor cap or rotor.
Normally, there should be battery voltage at the
“C” and “+” terminals. Low voltage would indicate
an open or a high resistance circuit from the dis-
tributor to the coil or ignition switch. If “C” terminal
voltage was low, but “+” terminal voltage is 10
volts or more, circuit from “C” terminal to ignition
coil or ignition coil primary winding is open.
Index
5C-74 - ELECTRONIC FUEL INJECTION (MULTI-PORT AND THROTTLE BODY)
90-823224--2 796
| Categories | Mercury MerCruiser Manuals |
|---|---|
| Tags | Mercury MerCruiser 454 CID, Mercury MerCruiser 502 CID |
| Model Year | 1993, 1994, 1995, 1996, 1997 |
| Download File |
|
| Document File Type | |
| Copyright | Attribution Non-commercial |
(4 votes, average: 4.5 out of 5)
Marine readers have rated 1993 1997 Mercury-MerCruiser GM V8 454 CID 7.4L and 502 CID 8.2L Marine Engines Service Manual Number 16 4.5 out of 5.0 based on 4 product reviews. Hugely helpful service manual! Perfect. Thank you!
Manuals are all Important for Technician
This book is invaluable if you do your own repairs. Great book.
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