Viking VGDO271, Сервисный журнал, Страница: 42 / 52

TESTING PROCEDURES
Service Information
Electronic Range Control (ERC) operates in
conjunction with a transformer/relay board 1, relay
board 2, and oven temperature sensor(s) to control all
bake, broil, and self-clean functions.
The ERC is connected to a mylar control panel
incorporating minute timer, clock, stop time, oven light,
cancel, bake, bake time, broil, and clean. Slew pads are
used to set times and temperatures.
The mylar control panel provides direct input to the
ERC to control all functions.
The ERC display consists of two digital readouts which
displays all timing functions, and all temperature
functions.
The transformer/relay board for upper oven consists of
oven light, bake, broil, door lock, and double line break
relays controlled by the ERC, and a step down
transformer with two secondary windings which
convert 120 VAC input to filament voltage (3.2--4.2
VAC) to power the ERC display.
The relay board for lower oven consists of bake, broil,
door lock, and double line break relays controlled by
the ERC.
Oven temperature sensor 1 is mounted in the upper
oven cavity and connected to the J4 connector on the
rear of the ERC. Oven temperature sensor 2 is mounted
in the lower oven cavity and connected to the J6
connector on the rear of the ERC. As the oven
temperature increased, the sensor resistance also
increases. The ERC converts this resistance to a
corresponding temperature readout and cycles the
relay(s) to maintain the desired temperature setting.
The ERC is also capable of sensing certain failure
conditions which can occur in the oven temperature
sensor(s), the self clean latch switch(es) the adaptor
board or the ERC itself. If the ERC senses a failure,
power will be removed from the relays, an alarm will
sound and a failure code will be displayed.
Each major component of the ERC system is serviced
as a separate part. However, each component and
related wire harness must be tested prior to replacing an
individual component.
Quick Test Procedure
“Quick Test” Mode for Electronic Range Control
Follow procedure to use the quick test mode. Entries
must be made within 32 seconds of each other or the
control will exit the quick test mode. The quick test
mode cannot be reactivated until power is disconnected
from oven, and must be accessed with in 5 minutes of
powering up.
NOTE: To enter Quick Test mode, this must be the
first key pad entered after power is applied.
1. Apply power to oven
press and hold BAKE TIME
(upper oven) pad for 5 seconds.
2. Display will read the following:
Pad Response
CLEAN Double Line Break (DLB) on
BAKE DLB and Bake on
BROIL DLB and Broil on
STOP TIME Panel light and beeper on
BAKE TIME Displays manufacturer code and
sensor readings “000" = open sensor
TIMER Displays dashes
CLOCK All display segments illuminated
OVEN LIGHT Oven light on
CANCEL Exit Quick test
SLEW Sequences through display segments
ERC Warnings and Failure Codes
The ERC is capable of detecting certain failures within
the ERC, along with oven temperature sensor and self
clean door latch switch.
The warning and failure codes which may appear on the
display:
ERC will flash “door”, if one full door lock cycle
has not been completed within 60 seconds of
energizing the door lock relay.
DIGIT FAILURE DISPLAY
F1 control malfunction - Replace ERC
F2 oven over temperature - Check sensor wiring,
sensor, and temperature limiter
F3 open sensor or sensor circuit - Check sensor
resistance and wiring
F4 shorted sensor or sensor circuit - Check sensor
resistance and wiring
F7 shorted input key - verify control panel to p.c.
board connection, test control panel continuity,
replace control panel
F9 failure of door lock switch sensing with door
unlocked - Check latch switch, door motor, check
plunger switch, and wiring.
FF failure of door lock switch sensing with door locked
- Check latch switch, door motor, check plunger
switch, and wiring
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