Input/Output Board - Bunn Fast Cup Series Service & Repair Manual

RIGHT PANEL
Input/Output Circuit Board (I/O)
Purpose: The I/O board receives and interprets the
input data it receives from the user touchscreen
assembly, resulting in a series of outputs to operate
components.

Input/Output Board

24.0VDC
Display Flow Meter
Pressure Trans-
Door Fan
Rear Fan BUNN Link
Brew Module R,C,L Bean
Home Sensor
All Valves
LED (Door)
TEST INSTRUCTION
Enter Service Technician Mode and Select
Service icon
Step 1: Select and enter the Voltage/Current tab.
Step 2: You can view the I/O board internal volt-
ages and the protected output circuit volt-
ages.
Volt/Ohm Meter - Voltage Check
Step 3: Disconnect or unplug machine from power.
Step 4: Remove right panel to access circuit
boards.
Step 5: Locate J11 connector on the Input/Output
board.
Step 6: Connect power to machine.
Step 7: Enable main On/Off switch.
Step 8: Set voltmeter on D/C voltage. Install red
meter lead on terminal J11-1 WHI/RED
wire (positive) and black meter lead on
J11-7 WHI/BLK wire (negative) terminal.
Step 9: The voltage reading should be 24.0VDC.
No voltage - Check for loose wire connect-
ion before going to 24V Universal Power
Supply.
PART RELATES TO THE FOLLOWING SYMPTOMS
• Machine is not On
• User touchscreen is not illuminated
5.0VDC 3.3VDC
Drip Tray Switch
Grounds Bin
ducers Switch
Swiper Switch
Detect
SERVICE
1
82
5
2
8