Chamberlain JDC Manual page 53

Troubleshooting (continued)
Display
Code
Message
F26 F26 OVER
VOLT
F31 F31 OPEN
F32 HELD
F33 F32 CLOSE
F34 HELD
F33 STOP
HELD
F34 SBC
HELD
Description Possible Causes Diagnosis
Motor drive AC input voltage
circuitry detected mis-selected
an overvoltage (120V/240V
condition models only)
Door imbalance
causes motor
regeneration
AC power out of
range
Wall control Wall control
buttons held/ buttons stuck
stuck for at least
1 minute.
Wiring short
Open/Close/
circuit
Stop/SBC inputs
triggered for at
least 1 minute.
Faulty accessory
connected to
OPEN/CLOSE/
STOP/SBC
terminals
Faulty LCD wall
control
Faulty powerhead
main board
Check whether the
transformer connector
is plugged in to the
connectors on the EMI filter
board marked '120V' or
'240V.'
Verify this matches the input
AC voltage supplied to the
operator.
Inspect door for imbalance
or broken springs
Verify input AC voltage:
Measure AC voltage
between 'L1' and 'L2'
terminals at EMI filter
board input connector.
Verify voltage is within
specifications.
If voltage is outside
specifications, see
resolution.
Check that all buttons return
to the normal state properly
when released.
Inspect wiring for open/
close/stop/SBC terminals
for short circuits
Disconnect accessories
from the terminals.
Swap wall control with
known-good unit
Remove all accessories
from OPEN/CLOSE/STOP/
SBC terminals. Ensure wall
control is replaced with
a known-good unit for
diagnosis.
53
Resolution
If 240V power is
applied when 120V is
selected, damage to
other components of
the operator electronics
may have occurred.
Ensure voltage selection
is corrected and verify
the operator functions.
repair or correct
conditions resulting
in excessive door
imbalance
Ensure the circuit
supplying the operator is
the correct voltage class
for the operator (e.g.
120V, 240V, or 480V)
If voltage is out of
specification for the
circuit, consult an
electrician.
Repair, clean, or replace
sticking buttons or
controls as necessary.
Correct any wiring faults
found
If problem is resolved by
disconnection of other
external accessories,
suspect a wiring issue,
faulty accessory, or
incompatible accessory.
If known-good wall
control resolves the
issue, fault is with
previous wall control
Try power cycling the
operator and restoring
factory defaults.
If problems persist,
replace powerhead main
PCBA