Failure Code [Ca449] Common Rail Pressure High Error 2 - Komatsu WA250-6 Shop Manual

SEN03843-00

Failure code [CA449] Common rail pressure high error 2

Action code Failure code
E03
Contents of
• Voltage (2) in common rail circuit is abnormally high.
trouble
Action of • Limits output and continues operation (limits common rail pressure).
controller
• Turns the centralized warning lamp and alarm buzzer ON.
Problem that
• Engine sound becomes larger under no load or light load.
appears on
• Engine output drops.
machine
• The input state (common rail pressure) from the common rail pressure sensor can be checked with
the monitoring function (Code: ENGINE, 36400, RAIL PRESS).
Related
• The input state (voltage) from the common rail pressure sensor can be checked with the monitoring
information
function (Code: ENGINE, 36402, RAIL PRESS).
• Method of reproducing failure code: Start engine
1 Defect in related system
2 Air in low-pressure circuit
Defective fuel return circuit
3
device
Possible causes
and standard
value in normal
state
Defective common rail pres-
4
sure sensor
5 Defective pressure limiter
6 Defective supply pump
22
40-330
Trouble
CA449
Causes
330 Troubleshooting by failure code (Display of code), Part 3
Failure code [CA449] Common rail pressure high error 2
Common rail pressure high error 2
(Engine controller system)
Standard value in normal state/Remarks on troubleshooting
• If another code is displayed, carry out troubleshooting for it.
Commingling of air with the low pressure circuit is suspected.
Inspect the circuit directly in the following procedure.
1) Remove the pressure pickup plug (outlet side) of the fuel main fil-
ter.
2) Operate the feed pump of the fuel pre-filter.
3) Inspect leakage of fuel and air from the pressure pickup plug.
a For check of pressure in fuel return circuit, see Testing and
adjusting, "Testing fuel pressure".
Fuel circuit pressure At low idle or cranking
a Prepare with starting switch ON, then carry out troubleshooting
without turning starting switch OFF.
Monitoring code
(Machine monitor)
Code: 36400,
RAIL PRESS
For testing of leakage from pressure limiter, see Testing and adjust-
ing, "Testing leakage from pressure limiter and return rate from
injector".
Leakage from pres-
sure limiter
If causes 1 – 5 are not detected, supply pump may be defective.
Max. 0.02 MPa
{Max. 0.19 kg/cm
Monitoring information
Condition when 0 – 0.39 MPa
engine stopped {0 – 4 kg/cm
At low idle 0 cc (No leakage)
WA250, 250PZ-6
1
}
2
}
2