Sharp R-408HS, Supplemental Service Manual

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6
R - 4 0 8 H S
Key Unit
Pin
NO. G1
Pin
NO. G13
Key unit ribbon cable
Key unit (Membrane Switch) front view
G10
G11
G12
G13
G9
G8 G7 G6 G5 G4 G3 G2 G1
POPCORN
9
3
6
2
5
8
0
1
4
7
TIMER
CLOCK
COOK
START
STOP
CLEAR
POWER
LEVEL
CLEAR
DEFROST
MINUTE
PLUS
REHEAT
*
*
*
*
When door is close, key can be operated.
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
J KEY UNIT TEST
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Using an ohmmeter and referring to the key unit matrix indicated on the control unit circuit, check the
circuit between the pins of the key unit that correspond to the CLEAR pad. When the pad is pressed,
the ohmmeter should indicate short circuit. When the pad is released, the ohmmeter should indicate
open circuit. If incorrect readings are obtained, the key unit is faulty and must be replaced. About the
other pads, the above method may be used.
5. Reconnect all leads removed from components during testing.
6. Re-install the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions.
6. Re-install the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions.
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
L DEFROST TEST
WARNING : The oven should be fully assembled before following procedure.
(1) Open the door.
(2) Place one cup of water in the center of the turntable tray in the oven cavity.
(3) Touch the " DEFROST " pad.
(4) Touch the number pad " 2 ".
(5) Touch the number pad " 5 ".
(6) Close the door.
(7) Touch the "START " pad.
(8) The oven is in Defrost cooking condition.
(9) The oven will operate as follows
MENU 1ST STAGE 2ND STAGE 3RD STAGE
STEAKS/CHOPS LEVEL TIME LEVEL TIME LEVEL TIME
0.5lb 60% 20sec. 40% 20sec. 30% 45sec.
(10) If improper operation is indicated, the control unit is probably defective and should be checked.