Yamaha F350B - Checking the ETV and TPS

5-23
Engine control unit and component
2. Measure:
• Engine ECM input voltage
Out of specification  Check the wire har-
ness for continuity.
a. Measure the input voltage between the en-
gine ECM coupler terminal 37 and ground.
b. Turn the “POWER” switch to ON, and then
measure the input voltage between the en-
gine ECM coupler terminal 53 and ground.
c. Turn the “POWER” switch to OFF.
d. Connect the engine ECM couplers.
Checking the ETV and TPS
TPS 1 and TPS 2 are components of the ETV,
which cannot be disassembled.
Do not loosen the throttle stop screw nut or
turn the throttle stop screw.
1. Measure:
• TPS 1 and TPS 2 output voltage
Out of specification  Check the TPS in-
put voltage.
a. Connect the YDIS to display “TPS 1” and
“TPS 2”.
b. Start the engine, warm it up for 5–10 min-
utes, and then stop it.
c. Turn the “POWER” switch to ON, and then
measure the TPS output voltages when
the Digital Electric Control lever is at the
fully closed position and fully open posi-
tion.
d. Turn the “POWER” switch to OFF.
Input voltage
12 V
Terminal 37–Ground
Input voltage (reference data)
11.6 V
Terminal 53–Ground
37
c
53
c
TPS 1 output voltage at throttle
valve fully closed (reference data)
0.972 V
TPS 2 output voltage at throttle
valve fully closed (reference data)
2.969 V
TPS 1 output voltage at throttle
valve fully open (reference data)
4.326 V
TPS 2 output voltage at throttle
valve fully open (reference data)
4.648 V