ELECTRICAL AND ECU
Repair
12-22
BY Service Manual
© 2009 Yanmar Marine International
REPAIR
Replace Engine Control Unit (ECU)
NOTICE: The ECU may be damaged if it is
powered when you unplug it. Turn the key switch to
OFF and disconnect the battery before
disconnecting the ECU from the electrical harness.
1. Disconnect the electrical panel power cables
from the battery, negative (-) cable first.
2. Remove the electrical panel cover.
3. Disconnect two electrical connectors
(Figure 12-23, (1)) from ECU.
Figure 12-23
Figure 12-23
4. Remove screws securing the upper ECU
retainer (Figure 12-23, (2)).
5. Loosen the lower attaching screws
(Figure 12-23, (3)) and remove the ECU.
6. Install the new control unit and tighten the
screws.
7. Connect the electrical connectors to the ECU.
8. Connect the electrical panel power cables to
the battery.
9. Check and delete any trouble codes that are
registered in the ECU after the work has been
completed.
Replace Coolant Temperature Sensor
1. Drain engine coolant. See Drain and Fill Closed
2. Remove intake manifold. See Intake Manifold
3. Remove electrical connector
(Figure 12-24, (1)) from sensor.
Figure 12-24
Figure 12-24
4. Remove sensor (Figure 12-24, (2)) from
cylinder head.
5. Installation is in reverse of removal.
6. Tighten sensor to 13.4 N·m (119 in.-lb).
7. Check and delete any trouble codes that are
registered in the ECU after the work has been
completed.
(1)
(2)
(
3
)
000
3
7
99
000
3
767A
(1)
(2)