Sub-Zero UC-24 series Service Manual page 4

Electronic Control System
MAIN CONTROL BOARD LAYOUT AND SUMMARY TABLE
Electrical connection points on the main control board are labeled alphanumerically. These labels correspond with
the alphanumeric summary table, located on the wiring diagram. By referencing the summary table, it is possible to
identify which components are connected at which points on the main control board. Below is a layout diagram of
the main control board, and a copy of a model UC-24C summary table. (See Figures 3-2 & 3-3)
NOTES:
• All components on the control board are non-replaceable. If a problem with the control board is identified, the
complete control board must be replaced.
• There is also a small control board in the control panel assembly (Not Shown). All components in the control
panel assembly are non-replaceable. If a problem with the control panel is identified, the complete control panel
assembly must be replaced.
J5
TERMINAL
120 VOLT CIRCUITS
P4
P3
P1
P2
J3-1
J3-2
J3-3
J3-4
J3-5
J3-6
J3-7
J2-1
J2-2
J2-3
J2-4
LOW VOLTAGE THERMISTOR CIRCUITS
J5-1,2
J5-5,6
J5-3,4
J5-7
J5-8
J6-1
J6-2
J6-3
J4-1
J4-2
J4-3
J4-4
J4-5
J4-6
#7003933 - Revision B - November, 2007
J4
PIN 1
PIN 1
PIN 1
J3
Figure 3-2. Main Control Board Layout
MAIN CONTROL BOARD SUMMARY
CIRCUIT DESCRIPTION
LN NEUTRAL
L1 POWER IN
COMPRESSOR COMPRESSOR
DEFROST DEFROST HEATER
FAN 1 EVAPORATOR FAN
NOT USED
ICE NOT USED
NOT USED
FAN 2 NOT USED
NOT USED
LIGHTS LIGHTS
R DOOR REF DOOR LIGHT SENSE
DEF DEFROST SENSOR
ICE NOT USED
NOT USED
CAB FREEZER COMPARTMENT
CAB REF COMPARTMENT
EVAP EVAPORATOR
EVAP EVAPORATOR
N BAFFLE NEUTRAL
C BAFFLE CLOSE
O BAFFLE OPEN
DISPLAY DISPLAY WIRING
DISPLAY DISPLAY WIRING
DISPLAY DISPLAY WIRING
DISPLAY DISPLAY WIRING
Figure 3-3. Main Control Board Summary Table
Under Counter (UC-24) Series
J6
PIN 1
P2 P1
FUNCTION
NEUTRAL INTO BOARD
POWER INTO BOARD
POWERS COMPRESSOR AND CONDENSER FAN
POWERS DEFROST CIRCUIT
POWERS EVAPORATOR FAN
POWERS LIGHTS
SENSES IF LOWER DOOR OPEN
SENSES WHEN DEFROST HEATER SHUTS OFF
SENSES FREEZER CABINET TEMP
SENSES REF CABINET TEMPERATURE
SENSES EVAPORATOR TEMPERATURE
SENSES EVAPORATOR TEMPERATURE
BAFFLE NEUTRAL
PULSED TO CLOSE NEUTRAL
PULSED TO OPEN NEUTRAL
12VDC POWER SUPPLY FOR DISPLAY BOARD
SERIAL DATA RECEIVE
SERIAL DATE TRANSMIT
GROUND FOR DISPLAY BOARD POWER SUPPLY
3-4
J2
PIN 1
P3 P4
COLOR
WHITE
BLACK
PURPLE
BLUE
RED
YELLOW
ORANGE
GRAY/WHITE
BLUE/WHITE
BLUE/BLACK
ORANGE/RED
BLUE/RED
YELLOW/RED
YELLOW/BLACK
YELLOW/WHITE
WHITE
RED
YELLOW
ORANGE