Komatsu PC210-8, Shop Manual

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UEN00240-01 40 Troubleshooting
44
PC210, 230, 240-8
Failure code [CA221] Ambient Press Sens High Error 1
User code Failure code
Trouble
Ambient pressure sensor high error
(Engine controller system)
E11 CA221
Contents of
trouble
• High voltage was detected in signal circuit of ambient pressure sensor.
Action of
controller
• Fixes ambient pressure value and continues operation.
Problem that
appears on
machine
• Engine does not start easily.
• Engine output lowers.
Related infor-
mation
• Signal voltage of ambient pressure sensor can be checked with monitoring function. (Code: 37401
Ambient pressure sensor voltage
• Method of reproducing failure code: Turn starting switch ON.
Possible causes
and standard
value in normal
state
Cause Standard value in normal state/Remarks on troubleshooting
1
Defective sensor power sup-
ply 1 system If failure code [ CA386 ] is also indicated, carry out troubleshooting
for it first.
2
Defective ambient pressure
sensor
a
Prepare with starting switch OFF, then turn starting switch ON
and carry out troubleshooting.
AMBAIR PRESURE Voltage
Between (1) – (2) Power supply 4.75 – 5.25V
Voltage is measured with wiring harness connected. Accordingly, if
voltage is abnormal, check wiring harness and controller, too, for
another cause of trouble, and then judge.
3
Hot short (Short circuit with
5V/24V circuit) in wiring har-
ness
a
Prepare with starting switch OFF, then turn starting switch ON
and carry out troubleshooting.
Wiring harness between CE01 (female) (3) –
AMBAIR PRESSURE (female) (3)
Voltage Max. 1 V
4
Short circuit in wiring har-
ness (with another wiring
harness)
a
Prepare with starting switch OFF, then carry out troubleshooting
without turning starting switch ON.
Wiring harness between CE01 (female) (3) –
AMBAIR PRESSURE (female) (3) and
between CE01 (female) (33) – AMBAIR
PRESSURE (female) (1)
Resis-
tance
Min. 100
k
z
5
Defective wiring harness
connector
Connecting parts between ambient pressure sensor – engine wiring
harness – engine controller may be defective. Check them directly.
• Looseness of connector, breakage of lock, or breakage of seal
• Corrosion, bend, breakage, push-in, or expansion of pin
• Moisture or dirt in connector or defective insulation
6 Defective engine controller
a
Prepare with starting switch OFF, then turn starting switch ON
and carry out troubleshooting.
CE01 Voltage
Between (33) – (38) Voltage 4.75 – 5.25 V