TROUBLESHOOTING
Troubleshooting Fuses, Relays and Harnesses
12/05
6LY3 Service Manual
13-21
© 2007 Yanmar Marine International
TROUBLESHOOTING FUSES, RELAYS AND HARNESSES
Fuse, Relay and Harness
When a harness short-circuits, in some cases, the fuse burns out. (A fuse never burns out under the usual
state of use.)
If the power supply of the peripheral device is taken from the engine harness without notice, the fuse may
burn out.
All of the fuses for the 6LY3 engine are shown in the table below.
Fuse Burns Out
1. When the location of the short circuit on the harness is found or when the causes of the short circuit are
clarified, repair as a temporary solution and replace the fuse. It is recommended to replace the harness
because of the possibility of decreasing waterproof quality on the harness and connector.
2. If the cause is undetermined, replace the fuse. If the fuse burns out again, replace the harness.
Test Check
Check the continuity by touching the corresponding fuse terminal to the ground. In the case of a fuse on a
relay assembly, open the fuse cover and check the continuity by touching the corresponding fuse terminal to
ground.
Checking a Fuse
1. Remove the fuse.
2. Check between both terminals for continuity.
3. If continuity is indicated, the fuse is in good condition.
No.
Fuse Size
Application
Fuse Location
Part No.
1
10A
AUX POWER
Fuse box
198535-52120
2
10A
IGN. PANEL
(Switch panel)
Fuse box
198535-52120
3
20A
ECU
Fuse box
198535-52140
4
10A
IGN. SIG
(Switch ON signal)
Fuse box
198535-52120
5
5A
YSDT
Fuse box
198535-52110
6
250A
Air Heater “A”
Below the exhaust manifold
119578-77150
7
250A
Air Heater “B”
Below the exhaust manifold
119578-77150
8
150A
ALTERNATOR
Below the exhaust manifold
119578-77090
9
50A
STARTER RELAY
Below the exhaust manifold
119578-77080
10
5A
IGN. SIG 1st Station
(Switch ON signal)
Rocker switch panel (1st Station)
170203-91930
11
5A
IGN. SIG 2nd Station
(Switch ON signal)
Rocker switch panel (2nd Station)
170203-91930