SEN00459-01 40 Troubleshooting
4 114E-3 Series
E-3 Code [122/CA122] Charge Air Press Sensor High Error 1
Error code Failure code
Trouble Abnormally high level in charge pressure sensor
122 CA122
Contents of
trouble
• High voltage is detected in pressure signal circuit of boost pressure sensor and temperature sensor.
Action of con-
troller
• Fixes charge pressure (101 kPa {1.03 kg/cm
2
}) and continues operation.
Problem that
appears on
machine
• Engine output drops.
Related infor-
mation
• Method of reproducing failure code: Starting switch ON.
Possible causes
and standard
value in normal
state
Causes Standard value in normal state/Remarks on troubleshooting
1
Defective sensor power sup-
ply 2 system
If failure code [CA227] is indicated simultaneously, carry out trouble-
shooting for it first.
2
Defective [pressure signal
circuit] of boost pressure
sensor, temperature sensor
a Prepare with starting switch OFF, then turn starting switch ON
and carry out troubleshooting.
BOOST PRESS & IMT Voltage
Between (1) – (4) Power supply 4.75 – 5.25 V
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 5
V, 24 V circuit) in wiring har-
ness
a Prepare with starting switch OFF, then turn starting switch ON
and carry out troubleshooting.
Wiring harness between J1 (female) (44) –
BOOST PRESS & IMT (female) (1)
Voltage Max. 1 V
4
Short circuit in wiring har-
ness (With another wiring
harness)
a Troubleshoot with starting switch OFF, then carry out trouble-
shooting without turning starting switch ON.
Wiring harness between J1 (female) (44) –
BOOST PRESS & IMT (female) (1) and
between J1 (female) (37) – BOOST PRESS
& IMT (female) (2)
Resis-
tance
Min.
100 kz
5
Defective wiring harness
connector
Connecting parts among boost pressure sensor, temperature sen-
sor, engine wiring harness, 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
6 Defective engine controller
a Prepare with starting switch OFF, then turn starting switch ON
and carry out troubleshooting.
J1 Voltage
Between (37) – (47) Power supply 4.75 – 5.25 V
To Next Page
Loading...
Need help?
General
