SCD-012-01-x Installation & Operation Manual
Document # 540106, Rev B, 06/2001
Page 12 of 16
6.4
Pinout Assignment and Descriptions
Pin #
Description
1
+ 28 VDC Power
2
Power Ground
3
R+ Audio Output
4
R- Audio Output
5
L+ Audio Output
6
L- Audio Output
7
Data Bus (A)
8
Data Bus (B)
9
Infrared Input +
10
Infrared Input -
11
IR Strap 2
12
IR Strap 3
13
IR Strap 4
14
IR Strap Common
15
Reserved
7.0
Post-Installation Test
28 VDC power has been connected to the unit. The audio signal output
of the unit is generally connected to cabin speaker systems in addition to
headphone locations. Verify all connections before supplying power to the unit.
8.0
Troubleshooting Guide
8.1
General Troubleshooting Procedures
Many problems can be isolated with the following general techniques:
•
To verify power to the unit, r28 VDC power is applied to
the proper pins on the unit. Use a voltmeter to verify correct level.
•
Reset by removing power from the unit for at least one minute and
reapply power. Verify the problem still exists.
•
Recheck all connections to the unit for security. Check all harness
runs for possible pinching.
Recheck all pinouts for application
accuracy.
•
To check data bus integrity, utilizing a voltmeter, “Oscilloscope” or
other voltage instrument, verify proper input voltage on the data bus
pins.
•
The RS-485 data bus is a bi-directional bus that does not have a
“bus controller”. The bus uses a differential digital signal that will
transmit only when commands are entered via switch selection or
other system synchronizing commands. The “A” leg of the bus is
HI and the “B” leg LOW.
