Inspection Of Mat (Manifold Temperature) Sensor; Inspection Of Fuel Feed Pump (Ffp); Inspection Of Throttle Position Sensor - TOHATSU MFS25 Service Manual

Electrical System
3) Inspection of MAT
(Manifold Temperature) Sensor
1. Measure ambient temperature.
2. Connect computer to outboard motor, and use diagnosis
system to display "Air Temperature (Intake Air
Temperature)".
3. Replace MAT sensor if difference between ambient
temperature and "Air Temperature (Intake Air Temperature)"
is over ± 5°C.
Perform inspection MAT sensor when engine is
cold.
4. Measure MAT sensor resistance. Replace if the resistance is
out of specified range.
This test can be made without removing parts.
MAT (Intake Air Temperature)
Sensor Resistance (Reference Value) :
2.35 to 2.55 Ω (at 20°C)
0.30 to 0.35 Ω (at 80°C)

4) Inspection of Fuel Feed Pump (FFP).

1. Use "Function Test or Air Purging" of diagnosis system to
inspect fuel feed pump (FFP) operation.
Check that fuel feed pump (FFP) 1 operation sound is
2.
heard. If not, check fuel system.
• This test can be made without removing parts.
• Fuel feed pump (FFP) operates two seconds
after performing "Air Purging".

5) Inspection of Throttle Position Sensor

1. Check throttle position sensor resistance. Replace throttle
body with throttle position sensor if other than specified
value.
Throttle Position Sensor Resistance :
Throttle Position
Blue - Black
Yellow - Black
Yellow - Blue
8-20
Fully Closed Fully Open
4.0 to 6.0kΩ
0.4 to 1.0kΩ 3.2 to 3.8kΩ
3.8 to 4.6kΩ 1.2 to 1.6kΩ
1
2
1 B (Black)
2 Y (Yellow)
3 L (Blue)
1
3
25/30 2006