Component Testing Chart - Jenn-Air JBC7624BS Technical Education

DIAGNOSTICS & TROUBLESHOOTING

Component Testing Chart

Unplug coffee system or disconnect power before performing
the following checks:
n A potential cause of a control not functioning is
corrosion on connections. Observe connections and
check for continuity with an ohmmeter.
n All tests/checks should be made with a VOM or DVM
having a sensitivity of 20,000 Ω per volt DC or greater.
n Check all connections before replacing components,
looking for broken or loose wires, failed terminals,
or wires not pressed into connectors far enough.
Damaged harness must be entirely replaced. Do not
rework a harness.
n Resistance checks must be made with power cord
unplugged from outlet, and with wiring harness or
connectors disconnected.
COMPONENT FROM
Display PCB Main Brd - J13
EV1, 3-Way Valve L1 Junction Block Main Brd - J1-2
EV2, 2-Way Valve L1 Junction Block Main Brd - J1-1
Fan, Cooling LED Fan PCB - J1
Flow Meter Main Brd - J7
Grinder Motor F2 (L1)
Hall Sensor Main Brd - J8
Coffee Heater L1 Junction Block Main Brd - F9 (N) 120 VAC
Steam Heater L1 Junction Block Main Brd - F8 (N) 120 VAC
Diverter Motor Main Brd - J1-5
Power In (Main Main Brd - F4 (L1) Main Brd - F5 (N) 120 VAC
Board)
Power In (LED LED Fan - F1 (L1)
Fan PCB)
NOTE: When each switch is activated, the control will beep (sound a tone).
5-12 Jenn-Air Built-in Coffee System
n
For Service Technician Use Only
COMPONENT TESTING CHART
TO VOLTAGE
Main Brd - J13 Pin 1 = +5 VDC
Pin 2 = TX BUS (MAX 5V)
Pin 3 = TX BUS (MAX 5V)
Pin 4 = GND
Pin 5 = - 7 VDC
Pin 6 = DATA OUT (MAX 5 VDC)
Pin 7 = DATA IN (MAX 5 VDC)
Pin 8 = CLOCK (MAX 5 VDC)
120 VAC
120 VAC
LED Fan PCB - J1 Pin 1 = +12 VDC (red)
Pin 2 = GND (black)
Main Brd - J7 Pin 1 - 2 = 5 VDC
Pin 1 - 3 = 0 VDC
Pin 2 - 3 = 5 VDC
Main Brd - F7 120 VAC
Main Brd - J8 Pin 1 = +5 VDC (black)
Pin 2 = Signal (max 5 VDC)
(gray)
Pin 3 = GND (gray)
Main Brd - J1-3 140 VDC*
LED Fan - F2 (N) 120 VAC
Do not continue with the diagnosis of the appliance if a fuse
is blown, a circuit breaker is tripped, or if there is less than
120+10%/-15% volt power supply.
The coffee system must be unplugged or the power
disconnected when measuring resistance.
When checking for proper voltage, complete the following
steps:
1. Disconnect power.
2. Connect voltage measurement equipment.
3. Reconnect power and confirm voltage reading.
4. Disconnect power after performing voltage
measurements.
RESISTANCE NOTES
N/A
458k ohms
444k ohms
N/A
N/A
13.1 ohms
N/A
11.5 ohms
15.4 ohms
62 ohms
N/A
N/A
Connector going to Display
PCB. Supplies circuit ground, +5
VDC, -7 VDC and transmission
lines. NOTE: 12 VDC is provided
when measuring the differential
between +5 VDC and -7 VDC.
3-Way Valve is grounded to heat
exchanger support.
2-Way Valve is grounded to
upper reinforcement, lower &
upper Main Brd cover, & heat
exchanger support.
Digital motor - resistance cannot
be measured.
Measures water used.
Can only be adjusted while
grinding.
Current sensor on the diverter
motor assembly that identifies
the position of the diverter
motor.
Dual heater element (23.ohms/
heater). Check TCO's if circuit
is open.
Check TCO if circuit is open.
*Voltage polarity reverses to
drive the motor up & down.
Main Brd AC IN
LED Fan PCB AC IN