TOHATSU BFT115A Service Manual page 105

MIL AND WARNING BUZZER DOES
NOT OPERATE
1. Fuse inspection
Turn the combination switch OFF.
Check for blown No.4, No.5, and No.9 fuses.
Is the fuse blown?
YES – Replace the blown fuse and check for
short in the main wire harness or incorrect
load by referring to the fuse load chart
(page 4-14).
NO – GO TO STEP 2.
2. ECM power line inspection
Install the No.4, No.5 and No.9 fuses in the fuse/
relay junction box.
Disconnect ECM connector B
Turn the combination switch ON.
Measure the voltage between the main wire harness
side No.8 (Yellow/Black) terminal of ECM connector
B and engine ground.
13
Measure the voltage between the main wire harness
side No.9 (Yellow/Blue) terminal of ECM connector
B and engine ground.
13
Does battery voltage present?
YES – GO TO STEP 3.
NO – GO TO STEP 4.
3. ECM ground line inspection
Turn the combination switch OFF.
Disconnect the ECM connector A
Check for continuity between the ECM connector A
main wire harness side No.17 (Green)
12
terminal, No.35 (Green) terminal and engine
ground.
Check for continuity between the ECM connector B
main wire harness side No.5 (Green/Black)
13
terminal, No.17 (Green/Red)
(Green/White) terminal, No.35 (Green/Red) terminal
and engine ground.
Is there continuity?
YES – Replace the ECM with a new one and
recheck.
NO – Repair open in the wire harness between
the ECM and engine ground.
.
13
.
12
PG3
(Green)
terminal, No.23
PG1
(Green/
Red)
TROUBLESHOOTING
ECM CONNECTOR B
MAIN WIRE HARNESS SIDE
13
ECM CONNECTOR A
MAIN WIRE HARNESS SIDE
12
PG4
(Green)
ECM CONNECTOR B
MAIN WIRE
HARNESS SIDE
13
PG2
(Green/
Red)
IGP 2
(Yellow/
Blue)
IGP 1
(Yellow/
Black)
LG1
(Green/
Black)
LG2
(Green/
White)
4-15