Throttle Position Sensor - Yanmar BY Series Service Manual

Component Tests
12/05

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
BY Service Manual
Figure 12-22
1 – Pin 1 - Ground (ECU pin 178)
2 – Pin 2 - Out (ECU pin 156)
3 – Pin 3 - 5V (ECU pin 130)
© 2009 Yanmar Marine International
ELECTRICAL AND ECU
0004167
Figure 12-22
Voltage Set-Point Values
Sensor Low Idle
PWG 1 0.70 to 0.80
PWG 2 0.31 to 0.43
High Idle
3.65 to 4.10
1.83 to 2.04
12-21