Parking Brake Is Released As Starting Switch Is Turned To On Position - Komatsu WA900-3E0 Shop Manual

E-5 Parking brake is released as starting switch is turned to ON
Failure
q
q
Related information
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No. Cause
1 Defective parking brake switch
Defective parking brake safety
2
relay L59
Defective parking brake emer-
3
gency release relay PL11
Hot short circuit in wiring harness
4
(short to power supply circuit)
WA900-3E0
E-5 Parking brake is released as starting switch is turned to ON position.
Parking brake is released when starting switch is turned to ON position.
Parking brake is applied when voltage (24 V) is not applied to parking brake solenoid.
Since parking brake switch is OFF during travel, voltage (24 V) is applied between pin C of
PL01 and pin 1 of F11 (when normal).
1. Turn starting switch to OFF position.
2. Disconnect PL01.
3. Start engine to charge accumulator, and then perform troubleshooting.
If parking brake is applied, parking brake switch is defective.
Replace parking brake safety relay L59 with another relay. If failure symptom
disappears, parking brake safety relay is defective.
Replace parking brake emergency release relay with another relay. If failure
symptom disappears, parking brake emergency release relay is defective.
1. Turn starting switch to OFF position.
2. Disconnect PL01.
3. Start engine to charge accumulator, and then perform troubleshooting.
Between ground and wiring harness connecting
of PL01 (female) (C), FL1 (17) and F11 (1)
Troubleshooting of electrical system (E-mode),
Procedure, measuring location, criteria and remarks
position.4 0 - 6 5
Voltage Max. 1 V
40-65