Battery Will Not Recharge - Mercury MerCruiser Service Manual

3. The DMT should indicate battery voltage. If battery voltage is not present, check the circuit breaker and battery power
interface for a loose or dirty connection or damaged wiring.
4. Connect the positive (+) DMT lead to the purple lead and the negative (–) DMT lead to the ground terminal.
5. Turn the ignition switch to the "ON" position.
6. The DMT should indicate battery voltage. If battery voltage is not present, check the ignition circuit (purple lead) for a loose
or dirty connection or damaged wiring.

Battery Will Not Recharge

Possible Cause
Excessive current draw from battery.
Alternator drive belt loose or in poor condition. Replace or adjust.
Unacceptable battery condition.
Loose or dirty electrical connections or
damaged wiring.
Faulty alternator
90-8M0099748 eng DECEMBER 2015
a
c
a
c
Turn off non‑essential accessories.
Test battery, replace if necessary.
Check all associated electrical connections and wires (especially battery cables).
Clean and tighten faulty connections. Repair or replace damaged wiring.
Test alternator output, replace if necessary.
a - Connector location
b - Purple and red/pink connector
c - Ground terminal
b
H z TEMP
m A
A
V
H z
mV
IG
OFF
IP
TEMP
A m A C O M V
H z
29371
a - Connector location
b - Purple and red/pink connector
c - Ground terminal
b
H z TEMP
m A
A
V H z
mV
IG
OFF IP
TEMP
A m A
C O M V H z
53695
Remedy
© 2016 Mercury Marine
Charging System
Page 4C-13