Starting Circuit Troubleshooting Flow Chart 2B-13 - Mercury 40 Service Manual

Starting Circuit Troubleshooting Flow Chart
No continuity indicated; there is an open circuit in the BLACK
NEGATIVE (-) battery cable between the NEGATIVE (-) battery
post and the powerhead.
Check cable for loose or corroded connections.
Check cable for open circuit.
No voltage reading;
proceed to TEST 3.
TEST 3
a. Reconnect BLACK ground wire(s).
b. Connect voltmeter between common engine ground and Test Point 3.
c. Turn ignition key to "Start" position.
No voltage reading;
proceed to TEST 4.
No voltage reading;
proceed to TEST 5.
No voltage reading;
proceed to TEST 6.
No voltage reading; check RED wire between
battery (+) positive terminal and Test Point 6.
90-852572R1 JANUARY 1998
Starter Motor Does Not Turn
SAFETY WARNING: Disconnect BLACK (starter motor)
cable from starter solenoid test point 1 BEFORE making
tests 1-thru-7 to prevent unexpected engine cranking.
TEST 1
Use an ohmmeter (R x 1 scale) and connect meter leads be-
tween NEGATIVE (-) battery post and common powerhead
ground.
TEST 2
a. Disconnect BLACK ground wire(s) from Test Point 2.
b. Connect voltmeter between common engine ground and Test Point 2.
c. Turn ignition key to "Start" position.
12 Volt Reading
Defective starter solenoid.
TEST 4
a. Connect voltmeter between common
engine ground and Test Point 4.
b. Turn ignition key to "Start" position.
TEST 5
Connect voltmeter between common
engine ground and Test Point 5.
TEST 6
Connect voltmeter between common engine ground and Test Point 6.
Continuity Indicated
Proceed to TEST 2
* Battery Voltage
12 Volt Reading*
Check BLACK ground wire for poor connection
or open circuit. Reconnect ground wire to starter
solenoid; proceed to TEST 7.
12 Volt Reading*
Neutral start switch is open, or YELLOW/RED
wire is open between Test Points 4 and 3.
12 Volt Reading*
Defective ignition switch.
12 Volt Reading*
Check fuse in RED wire between test points 5 and 6.
Check for open RED wire between test points 5 and 6.
ELECTRICAL - 2B-13