318
FORM 160.54-M1
ISSUE DATE: 10/25/2019
SECTION 34 - DIAGNOSTICS AND TROUBLESHOOTING
JCI COMPANY CONFIDENTIAL
JOHNSON CONTROLS
This diagnostic is used to verify correct operation of
the Serial Data Ports. There is a test for each of the six
serial data ports. Each RS-232 port (COM 1, 2 and 4b)
is tested by transmitting serial test data from outputs to
inputs of each port. Both the transmit and receive func-
tions as well as the control lines are tested. The RS-485
ports (COM 3, 4a, and 2) are tested by transmitting
serial test data from one RS-485 port to another. The
TX/RX opto-coupled port (COM 5) is tested by trans-
mitting serial test data from the TX output to the RX
input. If the received data matches the transmitted data,
PASS is displayed, indicating the serial port is OK.
Otherwise, FAIL is displayed, indicating the serial port
is defective. Prior to performing each test, the Service
technician must install a wire loop-back connection as
described below. See
manual for description of the Serial data Ports.
PROCEDURE
1. Using small gauge wire, fabricate loop-back con-
nections and install as follows for each port to be
tested. Failure to install the loop-back connection
or configure the microboard Program Jumper as
noted will result in a FAIL outcome for the test.
From To
COM 1
J2-4 (TX)
J2-3 (RX)
J2-5 (DTR) J2-2 (DSR)
From To
COM 2
J13-5 (TX) J13-3 (RX)
J13-7 (DTR) J13-1(DCD) and J13-2(DSR)
J13-4 (RTS) J13-6 (CTS) and J13-8 (RI)
RS-485 From To
(COM
J13-8 (+)
J11-3 (+)
2/4a)
J13-10 (-)
J11-2 (-)
This test applicable to software version
C.OPT.01.23.307 (and later). Microboard Program
Jumpers JP17 and JP27 must be installed in position
1 and 2.
RS-485 From
To
(COM
J12-3 (+)
J11-3 (+)
3 and 4a)
J12-2 (-)
J11-2 (-)
Microboard Program Jumper JP27 must be installed
in position 1 and 2.
From To
COM 4b
J2-7 (GTX) J2-6 (GRX)
Microboard Program Jumper JP27 must be installed
in position 2 and 3.
SERIAL INPUTS/OUTPUTS TEST SCREEN
LD15435
FIGURE 114 -
SERIAL INPUTS/OUTPUTS TEST SCREEN