Big Joe J1-192, Maintenance Repair Parts Manual, Page: 26 / 124

3-10 BL-J1-192-0315 - 11-19-2019
Table 3-3 Troubleshooting Chart (Traction/Lift Controller) - Continued
ERROR ERROR TEXT POSSIBLE CAUSE FAULT CLEARANCE
74 DRIVER SHORTED This alarm occurs when the voltage on
the main contactor is higher than
expected. This means that the main
contactor coil has a high voltage
although it is not supplied.
Replace the controller.
75 CONTACTOR DRIVER This alarm occurs when the voltage on
the main contactor is smaller than
expected. The main contactor has a
null voltage when supplied.
Check coils of the main contactor
(CNA#1) is not short circuited. If not,
replace the controller.
76 COIL SHORTED This alarm occurs when there is an over-
load on one of the following connec-
tions: CNA#1, CNA#3, CNA#4 or
CNA#6. Typically the problem is due to
a short circuit of one of the coils con-
nected to these outputs. After the over-
load has been removed, the alarm
automatically resets by releasing and
then enabling a travel demand.
Check the coils of main contactor
(CNA#1), electromechanical brake
(CNA#3), pump contactor (CNA#4),
and aux valve (CNA#6).
78 VACC NOT OK A test is made at key-on and after 20
sec that both the travel demands are
disactive. This alarm occurs if the
ACCELERATOR reading in the TES-
TER menu is higher than 1.0V (mean-
ing the wiper of the potentiometer is
higher than 2Vdc).
Check the mechanical calibration and
the functionality of the potentiometer.
80 FORW+BACK This alarm occurs when both the travel
demands (Fwd and Bwd) are active at
the same time.
Check the wiring of the Fwd and Bwd
travel demand inputs (use the readings
in the TESTER to facilitate the trouble-
shooting).
A failure in the logic is possible too.
When you verified the travel demand
switches are working properly and the
wiring is right, replace the controller.
79 INNCORECT START This is just a warning for an incorrect
starting sequence.
The possible reasons for this alarm are
(use the readings in the TESTER to
facilitate the troubleshooting):
1. A travel demand active at key on
2. The tiller switch active at key on
3. The H&S input active at key on
4. The Quick inversion active at key
on
A failure in the logic is possible too.
When all of the above conditions
checked OK, replace the controller.