MerCruiser 305 CID (5.0L) Service Manual page 357

INSTRUMENTATION
Switches
Ignition Key Switch
TESTING
Disconnect battery cables from battery before testing ignition key switch with wires
still connected to switch.
1. Disconnect battery cables, if testing ignition key switch with wires connected to switch.
2. With key switch in OFF position, there should be no continuity between switch terminals.
3. With key switch in RUN position, continuity will exist between switch terminals B to I.
There should no continuity between terminal S and any other terminals.
4. With key switch in START, continuity will exist between terminals B to I and B to S.
5. Terminals are to make contact at angles shown and to stay in contact condition as switch
is rotated toward START.
6. If ignition key switch tests bad, disconnect wire connections and remove switch. Test
switch again, as in Steps 2.-5. If switch tests good, wiring in harness is bad. There should
be no continuity between any harness wires with key switch removed.
Index
Page 4D-12
a - Key
b - Off
c - Continuity, B to I Terminals
d - Run
e - Continuity B to S Terminals
f - Start
CAUTION
f
e
d
c
b
a
Key View
SERVICE MANUAL NUMBER 24
B
S
I
Back View
90-861327--1 OCTOBER 1999
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