TCM FB-8 Series, Service Manual

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3. TROUBLESHOOTING GUIDE
(7) The pump motor is running when no load-handling operation is being performed.
(Applicable only to trucks with an EPS steering system)
20(YR)
20(YR)
5 V
0 V
0 V
5 V
(5) Only the lift lever does not work.
(6) Only the tilt lever does not work.
In maintenance mode:
C (Lift potentiometer
output voltage)
In maintenance mode:
C (Lift potentiometer
output voltage)
Lift potentiometer
GR189
WR188
YL94
Lift potentiometer
YL94
Below 0.2 V
4.8 V or more
0.5 to below 1.1 V
2.4 to 4.5 V
Pump motor inverter
Pump motor
inverter
Key switch ........... Turn it ON.
Tilt lever ................... Tilt fully.
Pump motor inverter
YR20
BL9
Tilt switch
YR20
BL9
OK
NG
GR189
WR188
YL94
OK
NG
YR20
YG21
YL22
OK
NG
Lift potentiometer
Check the harness between the pump motor inverter
unit (CN2P-8, -20, -32) and lift potentiometer.
Check the lift potentiometer.
Check the harness between the pump motor
inverter unit (CN1P-16, -17, -18) and each switch.
Tilt switch, ATT1 and ATT2 switches
Below 2.3 V
4.6 V or more
Key switch ............... Turn it ON.
Key switch ............... Turn it ON.
Lift lever ........................Pull fully.
Key switch ........... Turn it ON.
Pump motor
inverter
Pump motor inverter