Specifications

Curtis PMC 1223/33, 1225/35, 1227/37 Manual
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7 — DIAGNOSTICS & TROUBLESHOOTING
7
DIAGNOSTICS AND TROUBLESHOOTING
The 1223/33, 1225/35, and 1227/37 controllers provide diagnostics information
to assist technicians in troubleshooting drive system problems. The diagnostics
information can be obtained in two ways: observing the fault codes issued by the
Status LED or reading the appropriate display on the handheld programmer.
PROGRAMMER DIAGNOSTICS
The programmer presents complete diagnostic information in plain language.
Faults are displayed in the Diagnostic Menu, and the status of the controller
inputs/outputs is displayed in the Test Menu.
Accessing the Diagnostic History Menu provides a list of the faults that have
occurred since the diagnostic history file was last cleared. Checking (and clearing)
the diagnostic history file is recommended each time the vehicle is brought in for
maintenance.
The following 4-step process is recommended for diagnosing and trouble-
shooting an inoperative vehicle: (1) visually inspect the vehicle for obvious
problems; (2) diagnose the problem, using the programmer; (3) test the circuitry
with the programmer; and (4) correct the problem. Repeat the last three steps as
necessary until the vehicle is operational.
Example: A vehicle that does not operate in “forward” is brought in
for repair.
STEP 1: Examine the vehicle and its wiring for any obvious problems,
such as broken wires or loose connections.
STEP 2: Connect the programmer, select the Diagnostics Menu, and
read the displayed fault information. In this example, the display
shows “No Known Faults,” indicating that the controller has not
detected anything out of the norm.
STEP 3: Select the Test Menu, and observe the status of the inputs and
outputs in the forward direction. In this example, the display shows
that the forward switch did not close when “forward” was selected,
which means the problem is either in the forward switch or the switch
wiring.
STEP 4: Check or replace the forward switch and wiring and repeat the
test. If the programmer shows the forward switch closing and the
vehicle now drives normally, the problem has been corrected.
Refer to the troubleshooting chart (Table 8) for suggestions covering a wide range
of possible faults.