TOHATSU BFT75A Service Manual page 182

dummyhead dummyhead
DTC 141-1, 141-2 (ECT SENSOR 3 VOLTAGE IS TOO LOW OR TOO HIGH)
ECM
5V
TOH2
SG2
Bl BLACK Br BROWN
Y YELLOW O ORANGE
Bu BLUE Lb LIGHT BLUE
G GREEN Lg LIGHT GREEN
R RED P PINK
W WHITE Gr GRAY
DTC 141-1 (ECT SENSOR 3 VOLTAGE IS TOO LOW)
1. Symptom reproduction test
Turn the combination switch OFF.
Disconnect the ECT sensor 3 (2P) connector
ECM connector A
and joint connector 2
them.
Clear the DTC (page 5-5).
• Continue the procedure if the DTC does not
clear.
Turn the combination switch ON.
Measure the ECT sensor 3 voltage using the Dr.H.
Is the measurement within 0.08 – 4.92 V?
YES
NO
2. ECT sensor 3 signal line short circuit inspection
Turn the combination switch OFF and disconnect
the ECT sensor 3 (2P) connector
Turn the combination switch ON.
Measure the voltage between the ECT sensor 3
(2P) connector
(Red) terminal and engine ground.
Is the measurement within 4.75 – 5.25 V?
YES
NO
29
R
G
28
JOINT CONNECTOR 2
, ECM connector B
, and then reconnect
– Temporary failure (code
reappear)
– GO TO STEP 2.
main wire harness side No.1
– Replace ECT sensor 3 with a new one and
recheck.
– Repair short in the Red wire. If the main
wire harness is normal, replace the ECM
with a new one and recheck.
G G
21
22
12
,
,
does not
.
ECT SENSOR 3 (2P) CONNECTOR
MAIN WIRE HARNESS SIDE
FUEL SYSTEM
ECT
SENSOR 3
18
R
G
TOH2
(Red)
5-41