Checking Protective Diode V6; No Microwave Power - Diagnosis Procedure - Miele H 408 BM Series Technical Information

Technical Information
4.17

Checking Protective Diode V6

1. Remove the appliance from its cabinet; see Section 011-4.3.
2. Remove the screws securing the appliance lid. Remove the lid.
Danger!
Before performing any service or repair work, discharge the high-voltage
capacitor. See Section A-2.
3. Pull both connectors off the protective diode.
4. Use an ohmmeter with at least 500 volts of measuring capacity to
measure the resistance between the leads in both directions.
5. The reading should be infinite ∞ in both directions.
Danger!
After installation/repair is completed, as a matter of standard practice, the
appliance has to be checked for a tight seal with a microwave leak detector,
paying particular attention to the door and the housing edges.
4.18 No Microwave Power – Diagnosis Procedure
The following procedure should be used in the event that an H 408x BM
speed oven is reported as "the microwave function is not working", but other
aspects of the appliance are in functioning order.
This procedure will quickly isolate the fault to the appropriate circuit and/or
component(s).
Caution!
Parts of this procedure are performed while the appliance is connected to
live power.
Do NOT deviate from this procedure or skip steps unless instructed to within
the procedure. Skipping steps can produce inconclusive results.
Warning!
Do NOT attempt to operate the microwave system at any time during this
procedure.
Perform the high-voltage capacitor discharge procedure before testing any
components within the high-voltage circuit. Refer to Section A-2.
Procedure overview:
Perform door switch checks (sections 4.18.1 and 4.18.2), replacing
appropriate component(s) as necessary.
If ALL door switches check okay, proceed to Section 4.18.3 (as directed).
4.18.1 Door Switch 1F6 and 2F6 Test
1. Access the terminal block and verify that the appliance is being supplied
with the proper electrical supply (L1, L2, neutral and ground). Ensure that
live lines are on separate phases.
2. Ensure that the oven door is closed.
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H 408x BM