Sharp R-1510 Service Manual page 13

PROCEDURE
LETTER
(8) The oven will operate as follows.
Menu
Steaks/Chops
0.5lbs
(9) If improper operation is indicated, the control unit is probably defective and should be checked.
P FOIL PATTERN ON THE PRINTED WIRING BOARD TEST
To protect the electronic circuits, this model is provided with a fine foil pattern added to the primary on
the PWB, this foil pattern acts as a fuse.
1. Foil pattern check and repairs.
1) Disconnect the power supply cord.
2) Open the door and block it open.
3) To discharge high voltage capacitor, wait for 60 seconds.
4) Remove the control unit, referring to the procedure of " CONTROL PANEL ASSEMBLY,
CONTROL UNIT AND KEY UNIT REMOVAL ".
5) Follow the troubleshooting guide given below for repair.
STEPS
1
2
6) Make a visual inspection of the varistor.
Check for burned damage and examine the
transformer with a tester for the presence of
layer short-circuit (check the primary coil
resistance which is approximately 780Ω ±
10%). If any abnormal condition is detected,
replace the defective parts.
7) Reconnect all leads removed from
components during testing.
8) Re-install the control unit to the control panel
and re-install the control panel to the oven.
9) Reconnect the power supply cord.
10) Run the oven and check all functions.
2. Follow the troubleshooting guide given below, if indicator does not light up after above check and
repairs are finished.
1) Disconnect the power supply cord, and then remove outer case. Refer to procedure of " HOOD
EXHAUST LOUVER REMOVAL ", " REMOVAL OF OVEN FROM WALL " and " OUTER CASE
REMOVAL ".
2) Open the door and block it open.
3) To discharge high voltage capacitor, wait for 60 seconds.
4) Remove the hood intake duct R.
5) Disconnect the leads to the primary of the power transformer.
6) Ensure that these leads remain isolated from other components and oven chassis by using
insulation tape.
7) After that procedure, re-connect the power supply cord.
8) Follow the troubleshooting guide given below for repair.
STEPS
1
2
TEST PROCEDURES
COMPONENT TEST
1ST STAGE 2ND STAGE
LEVEL TIME LEVEL
60% 57sec. 40%
OCCURRENCE
Only pattern at "a" is broken.
Pattern at "a" and "b" are broken.
OCCURRENCE
The rated AC voltage is not present between
the normal open terminal of the relay RY2 and
the normal open terminal of the relay RY1.
The rated AC voltage is present at primary
side of low voltage transformer.
11
TIME
17sec.
CAUSE OR CORRECTION
*Insert jumper wire J1 and solder.
*Insert the coil RCILF2003YAZZ between "c" and "d".
d
a
b
c
CAUSE OR CORRECTION
Check supply voltage and oven power cord.
Low voltage transformer or secondary circuit defective.
Check and repair.
R-1510
R-1511