Hitachi ZW370 Technical Manual page 36

ZW370 FS 00-20
00 General Information
Outline
Cautions regarding welding repair service
If welding is needed to repair the chassis, observe the
following precautions to protect the hydraulic cylinders,
hydraulic units, gear sets, and electrical units from pos-
sible damage.
Cautions
1. Turn the starter switch OFF.
2. Remove the battery terminals both positive and
negative sides from the battery.
IMPORTANT
If a battery terminal is removed from a machine in
less than 30 seconds after the key is put into the
"OFF" position, it can corrupt the ECM program,
which can disable the engine. Always wait 1 full
minute to be sure to be past this "write to memory
function" prior to removing battery terminals.
3. Disconnect the connector for MCU (machine con-
troller), ECM (engine controller) and air conditioner.
Example 1
Section to be welded
Example 2
Do not ground this section.
Electric current may flow
through the cylinders.
Ground this section.
(correct grounding)
Section to be welded
4. Ground the welder near the section to be welded.
5. To ground the welder, check that the electric current
will not flow through the cylinders.
Cylinder head covers for some models have a low
conductive metal that will cause spark if the welding
current flows. The spark may damage the cylinder
rod.
6. Calibrate throttle pedal to ECM.
(a) Turn the starter switch to "ON".
(b) Fully depress and release the throttle pedal
three times.
(c) Turn the starter switch to "OFF".
Do not ground this section.
Electric current may flow
through the cylinders.
Ground this section.
(correct grounding)
35C00002
35C00006