Komatsu PC58UU-3 User Manual

PC58UU-3 20-331
TROUBLESHOOTING
E-16 Error code [78] (Abnormality in motor stall system) is displayed
a Abnormality in the motor stall system is displayed if the motor does not follow up 10 seconds after the dial is
operated. In the meantime, check that the input signal and relay output are normal with the monitoring func-
tion.
Cause Remedy
For condition of bit, see actions
of controller taken when trouble
occurs and phenomena of
machine.
1
Is monitored value normal?
NO
YES
• Turn starting switch ON.
• Current must be below 4 A
when normal.
When dial is increased:
(1) side (+), (4) side (–)
When dial is decreased:
(1) side (–), (4) side (+)
2
Is current between F22 (female) (1)
(Motor (+)) and (4) (Motor (–)) normal?
NO
YES
Development motor
(drive system)
Replace motor
• Resistance between (1) and
(2) of each relay: 96 z ± 10%
• Operation of each relay
(When starting switch is
turned ON)
When in neutral, (3) and (6)
are connected to each other.
When dial is increased, R5
and R4 (3), (5) are connected
to each other.
When dial is decreased, R5
and R3 (3), (5) are connected
to each other.
3
Do relays R5, R4, and R3 operate nor-
mally?
NO
Defective relay Replace
YES Disconnection or defective
contact in wiring harness
between F22 (female) (1), (4)
– R3 (female) (3), R4
(female) (3)
Repair or
replace
4
• Disconnect G3 and F22.
• Resistance between pins:
Max. 1 z
• Resistance between each pin
– chassis: Min. 1 Mz
Is resistance between G3 (female) (19)
– F22 (female) (5), G3 (female) (29) –
F22 (female) (6), G3 (female) (39) –
F22 (female) (3) and between each wir-
ing harness – chassis normal?
Disconnection or defective
contact in wiring harness
(having defective resistance)
between G3 (female) (19),
(29), (39) – F22 (female) (5),
(6), (3)
NO
Repair or
replace
YES
• Turn starting switch ON.
• When dial is increased:
Between G3 (19), (39) – (23):
10 - 16 V
• When dial is decreased:
Between G3 (29) – (23):
10 – 16 V
5
When dial is operated, is each input
signal normal?
NO
Defective motor (signal sys-
tem)
Replace
YES
Defective controller Replace
E-16
(6)

Komatsu PC58UU-3 Specifications

General

Brand	Komatsu
Model	PC58UU-3
Category	Construction Equipment
Language	English