Clark GEX20 - Page 162

Group 19, Motor Controls
19-3-12 • CONTROL TROUBLESHOOTING SM 765, Dec ’06
Fault
Code
Fault Name Fault Description Control Troubleshooting
Action
Required
172 "VMN
LOW"
Wrong voltage on
motor power out-
puts; failure in the
power section or
in the mosfet
driver circuit or in
the motorPUMP
• This fault signals that the under voltage /
over voltage protection interrupt has
been triggered Two possible reasons:
• A real under voltage / over voltage situa-
tion happened.
• Fault in the hardware section of the con-
troller that manages the over voltage pro-
tection.
• A problem with motor connection or
power circuit.
• Check if all 3 phases are correctly con-
nected.
• Check for short between motor terminal
and chassis
• Perform diode test
• Diode test
−Disconnect all power and motor leads
from control.
−Select diode test on your multi meter.
−Place positive meter lead on control -
Battery terminal place negative meter
lead on terminals U,V,W meter should
read .3V to .5V if not replace control.
−Place negative meter lead on control +
Battery terminal place positive meter
lead on terminals U,V,W meter should
read .3V to .5V if not replace control.
−If code presist replace control
Replace con-
troller
173 "VMN
HIGH"
Wrong voltage on
motor power out-
puts; failure in the
power section or
in the mosfet
driver circuit or in
the motor
PUMP • This test is carried out during initial diag-
nosis and in standby. Possible causes:
• Problem with motor connections or the
motor power circuit; check if the 3
phases are correctly connected; check if
there's chassis ground of the motor to
truck frame.
• unhook battery at controller and do a
diode check between Batt + and Batt -
(should read .3 to .5 volts)
• Fault in the inverter power section.
• Possible bad battery, Excessive voltage
to case of battery.
Replace con-
troller
174 "TH
MOTOR
SENSOR
KO"
Warning:Motor
Pump tempera-
ture sensor is out
of range
PUMP • The range of the motor temperature ana-
log sensor is always checked and a fault
is signaled if it's out of range
• When this fault occurs. The maximum
current is reduced to half and maximum
speed is reduced to 60 Hz.