Failure Code [Ca757] All Continuous Data Lost Error - Komatsu WA250-6 Shop Manual

330 Troubleshooting by failure code (Display of code), Part 3

Failure code [CA757] All continuous data lost error

Failure code [CA757] All continuous data lost error
Action code Failure code
E03
Contents of
• All data in engine controller are lost.
trouble
Action of
• Turns the centralized warning lamp and alarm buzzer ON.
controller
Problem that • Engine stops and sometimes cannot be started.
appears on
• The monitoring function of the machine monitor (engine controller system) sometimes fail to work
machine
normally.
Related
• Method of reproducing failure code: Turn the starting switch ON.
information
1 Defect in related system
Loose, corroded battery ter-
2
minal
3 Defective battery voltage
Defective fuse No. 4 of fuse
4
box FS1
Defective engine control cut-
5 out relay (L107) (Internal dis-
connection or short circuit)
Possible causes
and standard
value in normal
state
Defective engine control cut-
6 out relay (L108) (Internal dis-
connection or short circuit)
Disconnection in wiring har-
ness
7
(Disconnection or defective
contact in connector)
WA250, 250PZ-6
Trouble
CA757
Causes
All continuous data lost error
(Engine controller system)
Standard value in normal state/Remarks on troubleshooting
If another code is displayed, carry out troubleshooting for it.
Inspect battery terminal directly for loose and corrosion.
a Prepare with starting switch OFF, then carry out troubleshooting
with starting switch OFF and START.
Battery (1 piece)
Between (+) – (–) ter-
minals
If the fuse is broken, the circuit probably has a grounding fault, etc.
a Prepare with starting switch OFF, then carry out troubleshooting
without turning starting switch ON.
L107 (male)
Between (1) and (2)
a Prepare with starting switch OFF, then turn starting switch ON
and carry out troubleshooting.
When engine control cut-out relay (L107) is replaced with a relay of
the same type, if the condition becomes normal, the engine control
cut-out relay (L107) is defective.
a Prepare with starting switch OFF, then carry out troubleshooting
without turning starting switch ON.
L108 (male)
Between (1) and (2)
a Prepare with starting switch OFF, then turn starting switch ON
and carry out troubleshooting.
When engine control cut-out relay (L108) is replaced with a relay of
the same type, if the condition becomes normal, the engine control
cut-out relay (L108) is defective.
a Prepare with starting switch OFF, then carry out troubleshooting
without turning starting switch ON.
Wiring harness between fuse No. 4 of fuse
box FS1 – L107, L108 (female) (3)
Wiring harness between L107 (female) (5),
L108 (female) (5) – EC3 (female) (3), (4)
Wiring harness between EC3 (female) (1),
(2) – ground
SEN03843-00
Starting switch
OFF
START
Resistance
200 – 400 z
Resistance
200 – 400 z
Resis-
tance
Resis-
tance
Resis-
tance
1
Voltage
Min. 12 V
Min. 6.2 V
Max. 10z
Max. 10z
Max. 10z
35
40-330