Troubleshooting Guide; Troubleshooting And Repair - Hitachi WH 14DBDL Service Manual

1. Troubleshooting and Repair

Symptom Possible cause
(1) • Insufficient
No motor
connection of flat
motion
cable (B) of switch
• Switch connector
failure due to dust
or water
• Controller failure
due to dust or
water
• Stator FET PCB
failure due to dust,
water, or dropping
• Controller failure
due to dust, water,
and dropping
• Poor adhesion of
rotor pinion magnet
• Insufficient
connection of flat
cable (B) of switch
• Insufficient
connection of
connector cables
(A) and (B)
(2) • Insufficient
No switching
connection of
between
switch flat cable (B)
Forward and
Reverse • Switch connector
failure due to dust
and water
• Switch contact
failure

TROUBLESHOOTING GUIDE

• Check the connection of flat cable (B).
(See [1. Reassembly of the Wiring
Ass'y] on page 5.)
• Check flat cable (B) contact (for
corrosion, dust, water, and other
contaminant).
• Check switch connector (for corrosion,
dust, water, and other contaminant).
• Check the PCB surface (for dust,
water, and other contaminant).
• Check the PCB surface (for dust,
water, and drop-caused damage).
• Check the PCB surface (for dust,
water, and drop-caused damage).
• Check whether the magnet is securely
bonded to the rotor pinion.
• Check the connection of flat cable (B).
(See [1. Reassembly of the Wiring
Ass'y] on page 5.)
• Check connection of connector cables
(A) and (B).
(See [1. Reassembly of the Wiring
Ass'y] on page 5.)
• Check the flat cable (B) connection.
(See [1. Reassembly of the Wiring
Ass'y] on page 5.)
• Check the flat cable (B) contact (for
corrosion, dust, water, and other
contaminant).
• Check the switch connector state (for
corrosion, dust, water, and other
contaminant).
• When flat cable (B) is not defective
Troubleshooting
-1-
Repairing
• Securely connect
flat cable (B).
• Replace the DC-
Speed Control
Switch and the
controller.
• Replace the
controller.
• Replace the Stator
FET PCB.
• Replace the
controller.
• Replace the rotor
pinion.
• Securely connect
flat cable (B).
• Securely connect
connector cables
(A) and (B).
• Securely connect
flat cable (B).
• Replace the DC-
Speed Control
Switch and the
controller.
• Replace the DC-
Speed Control
Switch.