Testing The Stator Charge Windings; Regulator/Rectifier Diode Test - Mercury 15 EFI FourStroke Service Manual

• Check for loose or corroded battery connections.
• Visually inspect the wiring between the stator and battery for cuts, chafing, loose, corroded, or disconnected connection.
• Excessive electrical load from too many accessories will cause battery to run down.

Testing the Stator Charge Windings

NOTE: The test readings listed were taken at 20 °C (68 °F).
NOTE: The stator windings can be tested with the stator mounted to the engine.
1. Release the reusable cable tie that secures the stator leads.
2. Disconnect the yellow and white stator leads at the bullet connectors.
d
c
b
a
3. Connect an ohmmeter to the yellow and white stator leads to perform the following test.
NOTE: When measuring the resistance of 10 ohms or less using a digital ohmmeter, if the correct measurement cannot be
obtained, place the meter selector to a lower resistance range.
DMT 2004 Digital Multimeter
Meter Test Leads
Red
White
IMPORTANT: Be certain to secure the wires with the reusable cable tie, prior to placing the engine back into service.

Regulator/Rectifier Diode Test

IMPORTANT: When testing the regulator/rectifier diodes, use only a digital meter that has a diode inspection mode.
1. Release the reusable cable tie that secures the voltage regulator/rectifier leads.
2. Disconnect the yellow, white, and red voltage regulator/rectifier leads at the bullet connectors.
e
d
c
b
a
3. Connect the meter leads to the appropriate voltage regulator/rectifier leads to perform the following tests.
90-8M0125265 eng NOVEMBER 2017
Black
Yellow
a - Yellow stator wire
b - White stator wire
c - Bullet connectors
d - Reusable cable tie
62980
91‑892647A01
Meter Scale
Ω
a -
b -
c -
d -
e -
f
f -
62981
© 2018 Mercury Marine
Charging and Starting Systems
Reading
0.17–0.25 Ω
Red wire
Yellow wire
White wire
Bullet connectors
Reusable cable tie
Voltage regulator/rectifier
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