Hitachi ZAXIS 135US-5B Operator's Manual page 410

Drive Function
Problem
One or both side tracks are inoperable
Does not travel smoothly
Travel speed does not change
TROUBLESHOOTING
Cause
Damaged center joint
Incompletely released parking brake
Broken travel motor
Faulty pilot valve
Faulty pilot circuit line
Overly tensioned or slackened crawler sag
Lack of lubricant in front idler and/or roller
Deformed track frame
Embedded foreign matter such as rock
fragments
Dragged parking brake
Faulty travel mode switch
Faulty pressure sensor
Pump 1 and 2 delivery pressure sensors
Pumps 1, 2 control pressure sensors
Poor contact in connector
Damaged wire harness
Faulty controller (MC)
Faulty solenoid valve
Faulty motor
11-6
* Repair or replace
* Repair or replace
* Repair or replace
* Replace
* Repair or replace
Adjust
Refill
* Repair or replace
Remove
* Repair
* Replace
* Replace
* Replace
* Replace
* Repair or replace
* Repair
* Replace
* Repair or replace
* Repair or replace
Items with * mark: Consult your nearest Hitachi dealer.
Solution