Parking Brake Does Not Operate (As Emergency Brake) - Komatsu WA900-3E0 Shop Manual

Troubleshooting of electrical system (E-mode),
E-3 Parking brake does not operate (as emergency brake)
E-3 Parking brake does not operate (as emergency brake)
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Failure
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Related information
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No. Cause
1 Defective parking brake switch
2 Defective parking brake (solenoid)
Hot short circuit in wiring harness
3
(short to power supply circuit)
40-58
Parking brake does not
work.
Parking brake is applied when voltage (24 V) is not applied to parking brake solenoid.
Parking brake may be released by using parking brake emergency release connector in fuse
box.
Check output signal to parking brake interlock relay with monitoring function.
Code: 40990 "D-OUT-0" (ON: 1, OFF: 0)
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.
1. Turn starting switch to OFF position.
2. Disconnect F11.
3. Start engine and perform troubleshooting.
If parking brake is not applied, parking brake (solenoid) is defective.
1. Turn starting switch to OFF position.
2. Disconnect PL01.
3. Start engine to charge accumulator, and then perform troubleshooting.
Voltage
1) Although parking brake switch is set to ON position, parking
brake is not applied.
Procedure, measuring location, criteria and remarks
Between ground and wiring harness connecting
PL01 (female) (C), FL1 (17) and F11 (1)
4 0 - 5 8
Max. 1 V
WA900-3E0