Komatsu Galeo PC138US-8, Shop Manual

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40 Troubleshooting SEN02464-01
PC138US, USLC-8
17
Failure code [CA559] Rail press. low error 1
<How to use check sheet>
Carry out the above troubleshooting and take a record of the contents of the attached “Check sheet for no-
pressure feed“.
Note 1 : Check the low-pressure circuit parts for the following items.
1) Fuel level
2) Clogging of fuel tank breather
3) Sticking and wear of feed pump and clogging of filter
4) Leakage through and clogging of low-pressure fuel piping
5) Clogging of fuel filter
User code Failure code
Trouble
Rail press. low error
(Engine controller system)
E15 CA559
Contents of
trouble
• Supply pump does not feed fuel (level 1).
Action of
controller
• Limits common rail pressure.
Problem that
appears on
machine
• Output drops.
Related
information
• Common rail pressure can be checked with monitoring function.
(Code: 36400 Common rail pressure)
• Method of reproducing failure code: Start engine.
Possible causes
and standard
value in normal
state
Causes Standard value in normal state/Remarks on troubleshooting
1 Defective related system If another failure code is indicated, carry out troubleshooting for it.
2 Use of improper fuel Check fuel used directly (for high viscosity).
3 Clogging of fuel filter
a
If a fuel filter is clogged, replace it.
4
Defective low-pressure cir-
cuit device
a
For contents of troubleshooting, see Note 1. For check of pres-
sure in fuel low-pressure circuit, see Testing and adjusting,
"Testing fuel pressure".
Pressure in fuel low-pressure cir-
cuit
(At high idle or rated load)
-49 – 0 kPa
{-0.5 – 0 kg/cm 2 }
5
Defective electrical system of
supply pump IMV Supply pump IMV may have electric trouble. Carry out trouble-
shooting for following failure codes [
CA271 ], [ CA272 ].
6
Defective common rail pres-
sure sensor Common rail pressure sensor may be defective. Check wiring har-
ness for damage.
7 Defective pressure limiter
a
For testing of leakage from pressure limiter, see Testing and
adjusting, "Testing leakage from pressure limiter and return
rate from injector".
Leakage from pressure limiter Max. 20 cc/min (*)
*: A limit value is the value mentioned above, but a standard
value in normalcy is "0 cc/min. (no leak)".
8 Defective injector
a
For testing of return rate (spill) from injector, see Testing and
adjusting, "Testing leakage from pressure limiter and return
rate from injector".
Speed at rated operation Return (Spill) limit from injector
1,600 rpm 190 cc/min
1,700 rpm 200 cc/min
1,800 rpm 210 cc/min
1,900 rpm 220 cc/min
2,000 rpm 230 cc/min
9 Defective supply pump If causes 1 – 8 are not detected, supply pump may be defective.