Komatsu PC200-8M0, Shop Manual, Page: 831 / 1254

SEN06138-00
PC200, 200LC, 220, 220LC-8M0 40-400
9
400 Troubleshooting of electrical system (E-mode)
E-1 Engine does not start (Engine does not crank)
Cause Procedure, measuring location, criteria and remarks
6 Defective engine controller system
Engine controller power supply and ACC signal are diagnosed with proce-
dures for failure code
[DB2QKR], If failure code [ DB2QKR ] is displayed, per-
form troubleshooting for it first.
7
Defective starting switch, starter
cut relay R06, personal code relay
R07, battery relay, wiring harness
1. Turn starting switch to OFF position.
2. Remove fuse No.19 (30 A) in fuse box F01. (to prevent engine from starting
during check)
3. Insert T-adapters into connector E10.
4. Turn starting switch to START position and hold (two persons required for
this check).
Voltage Between E10 (1) and ground 20 to 30 V
a
If voltage is normal, proceed to cause 14.
8
Defective starting switch
(Internal open circuit)
1. Turn starting switch to OFF position.
2. Disconnect connector H15 and connect T-adapters to male side.
3. After troubleshooting, perform troubleshooting again with starting switch at
ON and START positions.
Between H15 (male) (1)
and (2)
Turn starting switch to
OFF position.
Resistance Min. 1 M
z
Turn starting switch to
ON position.
Resistance Max. 1
z
Between H15 (male) (1)
and (5)
Turn starting switch to
OFF position.
Resistance Min. 1 M
z
Turn starting switch to
ON position.
Resistance Max. 1
z
Between H15 (male) (1)
and (4)
Turn starting switch to
OFF position.
Resistance Min. 1 M
z
Starting switch: START Resistance Max. 1
z
9
Defective lock lever switch
(Internal open circuit)
1. Turn starting switch to OFF position.
2. Disconnect connector S14 and connect T-adapters to female side.
Between S14 (female) (1)
and (3)
Lock lever: FREE Resistance Min. 1 M
z
Lock lever: LOCK Resistance Max. 1
z
10
Defective starter cut relay
(Internal open circuit)
1. Turn starting switch to OFF position.
2. Replace starter cut relay (R06) with horn relay (R08).
3. Start engine.
If engine starts, original starter cut relay (R06) is defective.
11
Defective personal code relay
(internal open or short circuit)
a
If no failure is found by check on causell, this check is not.
1. Turn starting switch to OFF position.
2. Replace personal code relay (R07) with horn relay (R08).
3. Start engine.
If engine starts, original personal code relay is defective.
12
Defective diode D01
(internal open or short circuit)
1. Turn starting switch to OFF position.
2. Disconnect connector D01 and connect T-adapters to diode.
a
Check by using multimeter in diode range.
Between D01 (male) (1) (+) and (5) (-) No continuity
Between D01 (male) (5) (+) and (1) (-) Continuity
Between D01 (male) (2) (+) and (6) (-) No continuity
Between D01 (male) (6) (+) and (2) (-) Continuity