Thermador SMW272 B Service Manual page 76

Lower Oven Section
KEY PRESSED
Stop Time
Speaker will beep.
Clock All the display segments are lit.
Cook Time
Any error codes stored in the EEPROM will be displayed. The time digits will display the
last display head error code. The upper oven temperature digits will display the last up-
per oven relay board error code. The lower oven temperature digits will display the last
lower oven relay board error code. If no error codes exist, F0 is displayed.
The error codes stored in the EEPROM can be cleared by pressing and holding both the
COOK TIME and STOP TIME keys for 5 seconds while in the test mode.
0 - 9 Keys
Corresponding number is displayed in the blue digits.
The control will exit the test mode by two methods. First, by pressing either OFF key, and second, by using
a 16 second timer. Sixteen seconds after the last key action, the test mode will be cancelled.
TESTING THE TOUCH
CONTROL PADS
The control panel is comprised of the following (see the
illustration):
• Control Panel Frame (black, white, stainless
steel). The control panel brackets are mounted
on the frame and a bullet pin (see the small inset
at the top of the illustration) is screwed onto the
brackets.
• Control Panel Glass. The control board and
brackets are glued to the control glass.
The S-Model oven control panel is mounted to the front
subpanel with two bullet pins and four screws (see Page
46 in this manual for the removal procedure).
BRACKET
SCREW (4)
BEZEL
GLASS BRACKET
– +
R84
P3
– & + TEST PADS
A ribbon cable connects the control board to the touch
control board. One end of the cable has an edge connec-
Bullet
Pin
Screw
CONTROL BOARD
GLASS BRACKET
FRONT PANEL
GLASS ASSEMBLY
ACTION
tor that connects to the touch control board pins. The
pin connector on the board and the edge connector are
both indexed (the #4 pin is missing and the correspond-
ing #4 pin opening is plugged) to prevent the connector
from being reversed.
The touch control board has 28 touch pads, however,
not all of the pads are active. For example, a unit with no
lower oven convection feature will not have a position
on its control panel glass for that function. Thus, the
control board touch pad at that location will not be used.
The touch pads operate as follows:
1. An electromagnetic field surrounds each touch pad
so that when the glass over a pad is touched, the
field is disturbed.
2. The disturbance in the field is sensed by the micro-
processor on the touch control board as a mode,
or a command.
The touch control board has a positive and a negative
test pad (see the small inset at the bottom of the
illustration). To test the board:
1. Set a volt meter to read 10-volts D.C.
2. Touch the meter test probes to the bare foil
circles of the touch control board's positive and
negative test pads (do not touch the green solder
resist area at the centers).
• The meter should indicate 0-volts when a
touchpad is activated.
• The meter should indicate 5-volts D.C. when no
touchpad is activated.
Page 74
SMW Oven Service Manual