Yamaha F400A 2022 - Page 187

Outboard motor troubleshooting
4-14
124
125
TPS (Out of
specification)
“Check Engine” is displayed.
High engine idle speed.
Degraded acceleration perfor-
mance.
Declining maximum engine
speed.
Measure the TPS output volt-
age using the YDIS.
5-21
Check the ETV circuit. A-10
126
TPS (Out of
specification)
“Check Engine” is displayed.
High engine idle speed.
Throttle does not operate.
Engine speed is set at ap-
proximately 1500 r/min.
Measure the TPS output volt-
age using the YDIS.
5-21
Measure the TPS input volt-
age.
5-21
Check the ETV circuit. A-10
127
128
TPS (Out of
specification)
“Check Engine” is displayed.
Degraded acceleration perfor-
mance.
Declining maximum engine
speed.
Measure the TPS output volt-
age using the YDIS.
5-21
Check the ETV circuit. A-10
138
ETV (Engine
ECM internal
circuit malfunc-
tion)
“Check Engine” is displayed.
High engine idle speed.
Throttle does not operate.
Engine speed is set at ap-
proximately 1500 r/min.
Replace the engine ECM. 7-38
141
ETV (Throttle
valve malfunc-
tion)
“Check Engine” is displayed.
High engine idle speed.
Throttle does not operate.
Engine speed is set at ap-
proximately 1500 r/min.
Check the ETV circuit. A-10
142
ETV (Throttle
valve malfunc-
tion)
“Check Engine” is displayed.
Declining maximum engine
speed.
Check the throttle valve oper-
ation.
6-29
Replace the ETV. 6-28
143
ETV system
(Engine ECM
internal circuit
malfunction)
“Check Engine” is displayed.
High engine idle speed.
Throttle does not operate.
Engine speed is set at ap-
proximately 1500 r/min.
Replace the engine ECM. 7-38
Trou-
ble
code
Item (Condi-
tion)
Symptom Checking steps
See
page