SHARP R-5L16
Service Manual

R-5L16

TEST PROCEDURES (CONT'D) PROCEDURE LETTER COMPONENT TEST An open circuit thermal cut-out (OVEN) indicates that the foods in the oven may catch fire, this may be due to over heating produced by improper setting of the cooking timer or failure of the control panel.

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TIMER MOTOR (WITH VARI-SWITCH) TEST CARRY OUT 3D CHECKS before any of the following timer tests. TIMER SWITCH- CONTACTS Disconnect the leads from terminals described at following table. Connect an ohmmeter across terminals described at following table. Advance the timer and check that a short circuit reading is obtained on the meter. Turn the timer back to the zero (0) position and check that an open circuit reading is obtained on the meter. If these readings are not obtained then replace the timer. Disconnecting and checking terminals 1 and 2

TIMER - MOTOR Disconnect the leads from terminals described at following table. Connect an ohmmeter across the timer motor winding, terminals are described at following table, and check that a reading of resistance described at following table is indicated. If this reading is not obtained then the timer is probably defective and should be replaced. (Also refer to test procedure N.) Disconnecting and checking terminals Resistance of motor winding CARRY OUT 4R CHECKS after any of the above tests. 5 and 6 approximately 34.2 kohms

VARI SWITCH - CONTACTS
Before proceeding with this part of the test, check the relay coil as outlined above. WARNING: This test requires the oven to be operated with supply connected. Follow the instruction below carefully. 1. CARRY OUT 3D CHECKS 2. Disconnect the leads to the primary of the high voltage transformer. Make sure that the leads remain isolated from other oven components and chassis. 3. Disconnect the leads from terminals 3 and 4 of the timer, make sure that these leads remain isolated from other components and the oven chassis (use insulation tape if necessary). Do not disconnect leads from terminals 5 and 6. 4. Securely clip the leads of an ohmmeter across terminals 3 and 4 of the timer. (Make sure the meter can be read easily without being touched during the test.) 5. Close the door of the oven. 6. Connect the supply. 7. Set the TIMER to several minutes. 8. Without touching the meter or any part of the oven make a note of the time which the ohmmeter indicates Short and Open circuit in each power level as described in the table. 9. Set the MICROWAVE TIMER to 0 (zero). 10. CARRY OUT 3D CHECKS 11. Disconnect ohmmeter lead from terminal 4 of the timer. 12. Reconnect the lead of the panel harness to the terminal 4 of the timer. 13. Disconnect the lead from contact NC of vari switch. 14. Clip the lead of an ohmmeter to contact NC of vari switch. 15. Repeat steps 5, 6, 7, 8, 9 and 10. But in this time, the ohmmeter must indicate Short and Open circuit reversely against the table. 16. Disconnect ohmmeter leads from terminals 3 of the timer and contacts NC of vari switch. 17. Reconnect the leads to the primary of the high voltage transformer.

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