Code [431/Ca431] Idle Validation Switch Error - Komatsu 114E-3 Series Shop Manual

SEN00460-01
E-33 Code [431/CA431] Idle Validation Switch Error
Error code Failure code
431
Contents of trou-
• Abnormality occurred in idle validation switch circuit
ble
Action of
• Sets throttle angle to certain value and continues operation (depending on each model).
controller
Problem that
appears • Engine speed may not rise from low idle.
on machine
Related informa-
• Method of reproducing failure code: Starting switch ON, accelerator ON.
tion
1 Defective accelerator pedal
Disconnection in wiring har-
ness (Disconnection in wiring
2
or defective contact in con-
nector)
Possible
causes and
standard value
in normal state
Short circuit in wiring harness
3
(With another wiring harness)
Defective wiring harness con-
4
nector
5 Defective engine controller
12
Trouble Abnormality in idle validation switch
CA431
Causes Standard value in normal state/Remarks on troubleshooting
a Prepare with starting switch OFF, then carry out troubleshooting
without turning starting switch ON.
WAS1 (Male)
Between (5) – (4)
Between (6) – (4)
a Prepare with starting switch OFF, then carry out troubleshooting
without turning starting switch ON.
Wiring harness between J2 (female) (11) –
WAS1 (female) (5)
Wiring harness between J2 (female) (1) –
WAS1 (female) (6)
Wiring harness between J2 (female) (32) –
WAS1 (female) (4)
a Prepare with starting switch OFF, then carry out troubleshooting
without turning starting switch ON.
Wiring harness among all pins between J2
(female) (11) – J2 (female) (With also WAS1
disconnected)
Wiring harness among all pins between J2
(female) (1) – J2 (female) (With also WAS1
disconnected)
Connecting parts among accelerator pedal, engine unit wiring har-
ness, and engine controller are suspected. Inspect them directly.
• Loose connector, broken lock, broken seal
• Corrosive, bent, broken, forced-in, or extended pin
• Humidity in connector, entry of dirt or dust, poor insulation
a Prepare with starting switch OFF, then carry out troubleshooting
without turning starting switch ON.
J2 (Female)
Between (11) – (32)
Between (1) – (32)
40 Troubleshooting
Accelerator pedal
Release
Press
Release
Press
Resis-
tance
Resis-
tance
Resis-
tance
Resis-
tance
Resis-
tance
Accelerator pedal
Release
Press
Release
Press
1
Resistance
Max. 1 z
Min. 1 Mz
Min. 1 Mz
Max. 1 z
Max. 10 z
Max. 10 z
Max. 10 z
Min.
100 kz
Min.
100 kz
Resistance
Max. 1 z
Min. 1 Mz
Min. 1 Mz
Max. 1 z
114E-3 Series