TOHATSU BFT115A Service Manual page 255

ECT SENSOR 1/2/3/4 INSPECTION
Remove the following:
– ECT sensor 1 (page 5-116)
– ECT sensor 2 (page 5-117)
– ECT sensor 3 (page 5-117)
– ECT sensor 4 (page 5-118)
Heat the coolant with an electric heating element.
Suspend the sensor (1) in heated coolant and check the
continuity through the sensor as the coolant heats up.
• Wear insulated gloves and adequate eye protection.
Keep flammable materials away from the burner.
• Soak the sensor in coolant up to its threads with at
least 40 mm (1.57 in) from the bottom of the pan to
the bottom of the switch.
• Keep temperature constant for 3 minutes before
testing. A sudden change of temperature will result
in incorrect readings. Do not let the thermometer (2)
or sensor touch the pan.
Temperature
Resistance
Replace the sensor if it is out of specifications.
Install the following:
– ECT sensor 1 (page 5-116)
– ECT sensor 2 (page 5-117)
– ECT sensor 3 (page 5-117)
– ECT sensor 4 (page 5-118)
IAT SENSOR INSPECTION
Remove the engine cover.
Disconnect the IAT sensor 2P connector (1).
Measure the resistance at the sensor side connector
terminals.
25
Check that the resistance is within specifications in
each outside temperature range.
Install the engine cover.
40 °C (104 °F) 100 °C (176 °F)
1.0 – 1.3 kΩ 0.1 – 0.2 kΩ
(1)
Resistance:
Coolant temperature:
(1)
Resistance:
FUEL SYSTEM
(2)
Outside temperature:
5-137