Yanmar BY Series Service Manual page 219

Component Tests
12/05
Main Relay (K2)
12 V is supplied directly to terminal 30
(Figure 12-7, (4). An internal connection connects
one end of the winding to terminal 30. When the
key switch is turned ON, a 12 V signal is sent to
ECU terminal 27. The ECU then completes the
winding ground circuit (terminal 85) through ECU
terminal 232.
Figure 12-7
Figure 12-7
1 – Pin 2 - terminal 87
2 – Pin 4 - terminal 85
3 – Pin 5 - terminal 87
4 – Pin 6 - terminal 30
Results of Failed Relay
Failure of the relay results in loss of power to all
systems.
If this relay is defective, the following P-codes may
be generated.
• P0689 - short circuit to ground
• P0690 - short circuit to B+
Note: Viewed from bottom of connector.
BY Service Manual
0004173
© 2009 Yanmar Marine International
ELECTRICAL AND ECU
Fuel Pump Relay (K3)
12 V is supplied by fuse F3 to terminal 30
(Figure 12-8, (4). An internal connection connects
one end of the winding to terminal 30. When the
key switch is turned to ON, a 12 V signal is sent to
ECU terminal 87. The ECU then completes the
winding ground circuit (terminal 85) through ECU
terminal 220.
Figure 12-8
Figure 12-8
1 – Pin 2 - terminal 87
2 – Pin 4 - terminal 85
3 – Pin 5 - terminal 87 (not used)
4 – Pin 6 - terminal 30
Results of Failed Relay
Failure of the relay results in fuel supply pump will
not operate.
If this relay is defective, the following P-codes may
be generated.
• P0230 - power interruption - defective fuse (F3) or
relay or connections
• P0231 - regulation short circuit to Ground
• P0232 - regulation short circuit to B+
Note: Viewed from bottom of connector.
0004173
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