RS5320014 Rev. 0
22
Red Wire
to Cavity TCO
Current
Sense
Loop
High Voltage Board
Display Diagnostics
CS Current Sense
Current Sense – Indicates control is sensing low current
(Amp) draw. Check components which would allow unit
to run but produce no heat or low heat. Current sense
circuit is active only when using pre-programmed pads.
Time Entry feature will by-pass current sense circuit.
Red wire from cavity T.C.O. must be routed through
current sense loop on H.V. Board.
Possible Causes:
1. Interlock switch (contacts 2 & 3).
2. Open thermal cut-out (magnetron).
3. Open/loose wire.
4. Power relay.
5. H.V. Board.
6. Magnetron.
7. Diode.
8. Capacitor.
9. Transformer.
10.Triac.
S1 Watchdog - Membrane Touch Panel
Watchdog circuit verifies touch panel entry.
Possible Causes:
1. Shorted top touch panel.
2. Shorted side touch panel.
Testing
1. Disconnect power from oven.
2. Disconnect one touch panel ribbon cable from the
L.V. circuit board.
3. Plug oven in, open and close door to activate oven.
4. Wait approximately 60 seconds. If "S1" does not
appear in display, replace the disconnected touch
panel.
5. If "S1" re-appears in display, disconnect the other
touch panel and repeat steps 3 and 4.
HOT Magnetron Overheating
When "HOT" is displayed, the blower motor should be
operating.
Possible Causes:
1. Restricted air filter.
2. High ambient temperature.
3. Oven operated empty or with light loads.
4. Open control TCO.
5. Inoperative blower motor/wheel.
6. Open/loose TCO ground wire.
7. Open/loose E1 ground wire at H.V. board.
8. Inoperative high voltage board.
