Page 112
45-J Desel - Servce & Parts Manual
January 2022
Secton 19 - Troubleshootng
Troubleshooting Chart
The following chart describes the possible causes for inoperable functions of this machine. The
Causes and Solutions columns list various points of references that can be found in the Hydraulic,
Electrical, Schematics and Troubleshooting sections of this manual.
The majority of electrical troubleshooting on this model will require the use of the onboard EZ-Cal
scan tool, located inside the lower control box door. Please refer to “EZ-Cal Scan Tools” on page 99
for further instructions on the use of the EZ-Cal scan tool.
Perform a full assessment of machine operations prior to troubleshooting this model and using this
chart. This model is operated by a Microprocessor Control System equipped with a variety of built-
in safety interlocks to prevent continued operation in the event of a failure or misoperation. Some
interlocks may only be detected through the use of the EZ-Cal.
Problem
Possible Cause
Remedy/Solution
General Power Issue
No operation from upper
or lower control station.
No LEDs on modules.
Emergency stop switch pushed in,
or ignition switch turned off, or faulty
switches
Lower e-stop switch and ignition switch will cut all power.
Upper e-stop will cut only upper power as will the ignition switch in
platform control box.
Battery discharged or faulty cables
Will receive 4-4 or 7-7 flash on GP400. Clean, service and charge battery.
Repair cables.
Circuit breaker tripped
Located in lower control box. Look for short circuit and/or damage in wiring
or high amperage draw at valve coils or engine actuators.
Faulty Terminal Block Module
(TBM)
Located inside the lower control box. Initiates all power when signaled by
the key switch. Check for loose terminals.
Terminal 4 is Common power from Circuit breaker.
Terminals 1 and 2 are signals to close the relay.
No operation from upper
or lower control station
Module LEDs on or
flashing
Flash codes are the GP400’s
indication of a fault in the system.
Refer to flash code designation in this section of the manual or plug in an
EZ-Cal scan for more relevant information relating to the failure. See EZ-
Cal Instructions for more information.
Starter Relay or Starter failure
Test for signal and Common power to Starter Relay. Check fuse for
Common power to relay. Test Starter.
Operates from lower
controls but not from
upper controls. No LEDs
when in Upper control
position.
Base/Platform select switch not
in Platform position or switch
malfunction
Ensure that the switch is in the Platform position. Check switch function.
Damaged or loose harness
connections to upper control box
Check for power inside the upper control box on e-stop switch and at
Buss Module. Check for presence of ground on the Ground Buss Module.
Repair connections.
Malfunctioning GP440 Module
(Module inside the upper control
box)
Check help messages using the EZ-Cal tool. Also check for joystick inputs
(see 2C2 and 2D2 Diagnostic Chart for inputs from GP440).
System interlock
Check EZ-Cal HELP messages for interlock
Problem
Possible Cause
Remedy/Solution
Engine Related Issues
Starter will not crank from
upper or lower stations
Battery discharged or faulty cables
Will receive 4-4 flash on GP400. Clean, service and charge battery. Repair
cables.
Malfunctioning start relay or fuse
Test/replace relay located on left hand side of engine and fuse located
near starter
Malfunctioning starter
Test/replace starter
Faulty start switch either location
Test/replace as necessary
Starter interrupt system initiated
Check for red “Start Disable” light on lower panel. Starter may be operated
for 10 seconds before a 30 second “cool down” is initiated.
