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Troubleshooting (Dead Unit)
1. Check voltage at the house receptacle while it is
under load. Check for 240 VAC between L1 and
L2, 120 VAC between L1 and neutral, and 120
VAC between L2 and neutral.
• If voltage is incorrect, problem is with house
wiring.
• If voltage is correct, continue to next check.
Note:
To gain better access to components, remove
the wires that plug onto the large relays on the
Relay Board
(See
Relay Board
.
) and cut the wire tie
that the CN 103 wire harn ess is routed through.
2. Check voltage between Relay Board CN5 pins 1
and 3.
• If 120 VAC is present, go to
step 12.
• If 120 VAC is not present, continue to next
check.
3. Check voltage between Relay Board CN5 pin 3
and the output of the Bottom TCO.
• If 120 VAC is present, the wire from Relay
Board CN5 pin 1 to the Bottom TCO is open.
• If 120 VAC is not present, continue to next
step.
4. Check voltage between Relay Board CN5 pin 3
and the input of the Bottom TCO.
• If 120 VAC Is present, replace Bottom TCO.
• If 120 VAC is not present, continue to next
step.
5. Check voltage between Relay Board CN5 pin 3
and the Output of the Magnetron TCO.
• If 120 VAC is present, wire between the
Bottom TCO and Magnetron TCO is open.
• If 120 VAC is not present, continue to next
step.
6. Check voltage between Relay Board CN5 pin 3
and the Input of the Magnetron TCO.
• If 120 VAC is present, replace Magnetron
TCO.
• If 120 VAC is not present, continue to next
step.
7. Check voltage between Noise Filter 1 line and
neutral output.
• If 120 VAC is not present, go to step 11.
• If 120 VAC is present, continue to next step.
8. Check voltage between Relay Board CN5 pin 3
and Noise Filter 1 line output.
• If 120 VAC is not present, wire between CN5
pin 3 and Noise Filter 1 neutral out is open.
• If 120 VAC is present, continue to next step.
9. Check voltage between Noise Filter 1 neutral
output and the input of the Oven TCO.
• If 120 VAC is not present, wire between
Noise Filter 1 line out and the Oven TCO is
open.
• If 120 VAC is present, continue to next step.
10. Check voltage between Noise Filter 1 neutral
output and the output of the Oven TCO.
• If 120 VAC is not present, replace Oven TCO.
• If 120 VAC is present, wire is open between
the Oven TCO and Magnetron TCO.
11. Check voltage between Noise Filter 1 line and
neutral input.
• If 120 VAC is present, check Noise Filter 1
fuses, if OK, replace Noise Filter 1.
• If 120 VAC is not present, power cord or lines
from power cord to Noise Filter 1 is open.
12. Check voltage between Power Supply Board CN
1 pins 1 and 3.
• If 120 VAC is present, go to step 14.
• If 120 VAC is not present, continue to next
step.
13. Check voltage between Power Supply Board CN
1 pin 1 and Output of Bottom TCO .
• If 120 VAC is present, wire between CN1 pin
3 and the Bottom TCO is open.
• If 120 VAC is not present, wire between CN1
pin 1 and Noise Filter 1 neutral out is open.
(
Continued Next Page
)