Manitowoc 2250 - Page 315

Reference Only
Manitowoc Published 07-19-16, Control # 249-01 10-11
2250 SERVICE/MAINTENANCE MANUAL TROUBLESHOOTING
10
PROBLEM 9
No front or rear load drum operation.
POSSIBLE CAUSES
Load drum disc brake not releasing. Load drum pawl not released or hung up. No voltage through control handle to PC controller. No
voltage out of PC controller to pump EDC. Wiring or switch is bad.
CHECKS
Does diagnostic display DRUM 1, 2, or 3 screen (bank 5) display 1 and (bank 6) display 0 when handle is moved in
problem direction?
Yes No
Engine loads when moving problem handle in either direction?
Is drum brake switch in correct position?
Yes No
Yes
No
Use test plug adapter. (See Test 9—Checking
Voltage at the Hydraulic Brake Valve.) Is 12 volts
present at disc brake solenoid (80E, 81E, or 81EL)
when problem handle is moved?
Yes
No
Consult dealer/factory.
Move switch to
correct position.
Repair or replace wiring or switch.
Consult dealer/factory.
When moving problem handle in both directions, does DRUM 1, 2, or 3
diagnostic screen (bank 1) obtain 100% handle control in each direction?
Yes
No
Does drum turn while moving
handle and actuating manual
override on brake valve?
Replace valve.
Yes No
When moving problem handle in both directions,
does DRUM 1, 2, or 3 diagnostic screen (bank 2)
obtain 100% pump control in each direction?
Yes
No
Is voltage at handle (80P or 81P)
more than 0 with handle moved?
(See Test 12—Checking Voltage at
the Control Handle.)
Yes No
Is there an operating or system fault?
Correct problem.
Yes No
Consult dealer/factory.
Is pressure at brake more than
6 bar (90 psi)?
Repair or replace brake.
Yes No
Is system pressure more than
6bar (90psi)?
Readjust charge pressure
relief or replace pump.
Yes No
Replace brake valve.
Manually stroke pump. (See Test 10—Manually
Stroking the Pump.) Does pump pressurize?
Use test plug adapter. (See Test 4—Testing
the Pump EDC and Motor PCP.) Is voltage
present at pump EDC?
Yes No
Yes
No
Replace pump EDC.
Repair or replace wiring
or consult dealer/factory.
Is 10 volts at handle (87FA)?
Yes
No
Repair or replace handle.
Replace fuse F16 (87FA) and/or
wiring. (See Test 11—Testing for
Voltage at the Fuse Box.)
Isolate pump. (See Test 10—Manually Stroking the
Pump.) Does manually stroked pump pressurize?
Yes No
Repair or replace
motor.
Repair or replace
pump.