GE JVM1790SK - Profile 1.7 cu. Ft. Convection Microwave Service Manual page 32

(3) CHECKOUT PROCEDURES FOR CIRCUIT
BOARD
The following symptoms indicate a defective circuit
board.
1) The start function fails to operate but the high
voltage Systems, the interlock switches, the door
sensing and the relay check good.
2) The unit with a normal relay continuously operates.
3) Proper temperature measurement is not obtained.
4) The buzzer does not sound or continues to sound.
5) Some segments of one or more digits do not light
up, or they continue to light up, or segments light
when they should not.
NOTE: A MICROWAVE ENERGY LEAKAGE TEST MUST ALWAYS BE PERFORMED WHEN THE UNIT IS
SERVICED FOR ANY REASON.
(4) CHECKOUT PROCEDURES FOR CONVECTION
Convection or Combination does not operate.
Convection
Cook
• Remove neon light
• Program bake cook
• 225°F (use dial)
• Press start
• Display "PREHEAT OFFSET ON"
• Ready beep
• Cycle 225°F
• Do not clear
• Program cook time 1 min
• Press start
• Auto shut-off at set cook
time
YES
Control
system
normal
- PROBLEM (A) -
YES NO
Verity
control
xmfr
NO
Repair
Replace
or
smart
Replace
board
6) Wrong figures appear.
7) The figures of all digits.
8) Some of the indicators do no flicker light up.
9) The clock does not keep time properly.
Combination
Cook
• Program fast bake cook
• 225°F (use dial)
• Press start
• Display "PREHEAT 225 DEG"
• Ready beep
• Cycle 225°F
• Cbserve neon light
• Press start
• Do not clear
• Program fast back cook
time 2 min.
• Press start
• Neon cycle
• MW "ON" 13 sec then
MW "OFF" & heater "ON"
17 sec
• Auto turn "OFF" (2 min)
YES
•Verify control
Control
xfmr &
system
• Oven circuit
normal
• All normal except
• MW power
High volt.
Section
7-21
NO
Not
normal
Repair
or
Replace