Yanmar BY series, Service Manual

Page: 250 / 275

ELECTRICAL AND ECU
BY Service Manual 12-23
Component Tests
Camshaft Speed Sensor
This sensor measures the speed of the camshaft.
This value is compared with the crankshaft speed
by the ECU. It is mounted on the cylinder head
cover near the front of the engine.
Results of Failed Sensor
Failure of the sensor results in:
• Difficulty starting and reduction in power ( See
Engine Faults and Torque Limitations on
page 13-3.
)
If this sensor is defective, the following P-codes
may be generated:
• P0344 - disagreement between camshaft speed
sensor and crankshaft speed sensor
• P2614 - no connection / short circuit
Figure 12-21
1 – Pin 1 - 12V (Fuse F5)
2 – Pin 2 - F_out (ECU pin 1/87)
3 – Pin 3 - Ground (ECU pin 1/15)
Throttle Position Sensor
This sensor is located in the remote control head. It
communicates with the ECU with varying signals
based on throttle position. The ECU then calculates
the position of the throttle lever in percent, and
adjusts fuel injection to adjust engine speed. The
ECU supplies 5V and ground connections.
Results of Failed Sensor
Failure of the sensor results in:
• One failed sensor - limitation of the injection rate
( See Engine Faults and Torque Limitations on
page 13-3. )
• Two failed sensors - engine low idle will increase
If this sensor is defective, the following P-codes
may be generated:
• Sensor 1+2 (PWG):
• P0122 - both throttle signals are missing / short
circuit to ground
• P0222 - both throttle signals are missing / short
circuit to ground
• Sensor 1 only (PWG):
• P0123 - throttle signal 1 short circuit to B+
• P0122 - throttle signal 1 is missing / short
circuit to ground
• Sensor 2 only (PGS):
• P0223 - throttle signal 2 short circuit to B+
• P0222 - throttle signal 2 is missing / short
circuit to ground
Test Values
• At 0 bar (0 psi) (relative) - 0.5 V
• At 1800 bar (26, 107 psi) (relative) - 4.5 V
0004167