R-291KM - Sharp Home Appliance Service Manual (repair manual). Page 2

CONTENTS

CHAPTER 1. BEFORE SERVICING 
[1]  GENERAL IMPORTANT INFORMATION................1-1
[2]  CAUTION MICROWAVE RADIATION .....................1-1
[3] WARNING .....................................................................1-1

CHAPTER 4. APPEARANCE VIEW
[1] OVEN ..............................................................................4-1
[2]  TOUCH CONTROL PANEL.........................................4-1

CHAPTER 5. OPERATION SEQUENCE
[1] OFF 

CONDITION .........................................................5-1

[2] MICROWAVE 

COOKING 

CONDITION ...................5-1

[3]  SENSOR COOKING CONDITION..............................5-2

CHAPTER 6. FUNCTION OF IMPORTANT COMPO-
NENTS
[1]  DOOR OPEN MECHANISM.....................................6-1
[2]  DOOR SENSING SWITCH AND SECONDARY 
          INTERLOCK SWITCH.....................................................6-1
[3] MONITOR 

SWITCH 

.....................................................6-1

[4] FUSE 

T6.3A .................................................................6-1

[5] HIGH 

VOLTAGE 

FUSE 

.................................................6-1

[6]  TEMPERATURE FUSE 150C (OVEN) .......................6-1
[7] TURNTABLE 

MOTOR ................................................6-1

[8] FAN 

MOTOR .................................................................6-1

[9] HUMIDITY 

SENSOR......................................................6-1

[10]   NOISE FILTER ................................................................6-1

CHAPTER 7. TROUBLESHOOTING GUIDE
[1] FOREWORD ..................................................................7-1
[2] CHART ............................................................................7-1

CHAPTER 8. TEST PROCEDURES
[1]  Procedure A: MAGNETRON (MG) TEST...............8-1
[2]  Procedure B: HIGH VOLTAGE TRANS-

FORMER TEST ..............................................................8-2

[3] Procedure C: HIGH VOLTAGE RECTIFI-

ER TEST ..........................................................................8-2

[4]  Procedure D: HIGH VOLTAGE CAPACI-

TOR TEST .......................................................................8-2

[5]  Procedure E: SWITCH TEST .....................................8-2
[6]  Procedure F: TEMPERATURE FUSE 

TEST ...............................................................................8-3

[7]  Procedure G: MOTOR WINDING TEST.................8-3
[8]  Procedure H: FUSE T6.3A ........................................8-3
[9]  Procedure I: HIGH VOLTAGE FUSE TEST ..............8-3
[10]  Procedure J: TOUCH CONTROL PANEL 
          ASSEMBLY TEST...........................................................8-4
[11]  Procedure K: KEY UNIT (MEMBRANE SWITCH) 
          TEST..................................................................................8-4
[12]  Procedure L: RELAY TEST..........................................8-5

[13]  Procedure M: PROCEDURES TO BE TAKEN 
          WHEN THE THERMAL FUSE IN LOW VOLTAGE 
          TRANSFORMER ON THE PRINTED WIRING
          BOARD (PWB) IS OPEN...............................................8-5

[1]  OUTLINE OF TOUCH CONTROL PANEL..................9-1
[2]  PRECAUTIONS FOR USING LEAD-FREE SOLDER.9-1
[3]  SERVICE FOR TOUCH CONTROL PANEL..........................9-2

ADJUSTMENT PROCEDURE
[1] BEFORE 

OPERATING ................................................... 10-1

[2]  OUTER CASE REMOVAL ............................................. 10-1
[3] HIGH 

VOLTAGE 

TRANSFORMER 

RE-

MOVAL ........................................................................... 10-2

[4] 

HIGH VOLTAGE RECTIFIER ASSEMBLY, 

HIGH VOLTAGE FUSE AND HIGH VOLT-
AGE CAPACITOR REMOVAL .................................... 10-2

[5] MAGNETRON 

REMOVAL .......................................... 10-2

[6]  POSITIVE LOCK CONNECTOR (NO-

CASE TYPE) REMOVAL ...............................................10-2

[7] TURNTABLE 

MOTOR 

REMOVAL ................................10-3

[8] COOLING 

FAN 

MOTOR 

REMOVAL...........................10-3

[9]  POWER SUPPLY CORD REPLACE-

MENT.................................................................................10-4

[10] CONTROL PANEL ASSEMBLY REMOV-

AL .....................................................................................10-4

[11]  GRAPHIC SHEET AND MEMBRANCE SWITCH 
          REPLACEMENT...............................................................10-4
[12] DOOR SWITCH, SECONDARY INTERLOCK 
          SWITCH AND MOTOR SWITCH REMOVAL............10-5
[13]  DOOR SWITCH, SECONDARY INTERLOCK 
          SWITCH AND MOTOR SWITCH ADJUSTMENT.....10-5
[14] DOOR REPLACEMENT..................................................10-5

CHAPTER 12. CIRCUIT DIAGRAMS
[1] Oven 

Schematic ........................................................ 12-1

[2] Pictorial 

Diagram 

(Figure 

S-1)

[3]     Control unit circuit (Figure S-2)............................ 12-3
[4]     Control unit circuit (Figure S-3)............................ 12-4
[5]     Printed Wiring Board (Figure S-4)........................ 12-5

.............................. 12-2

R-291(K)M