6.10.1 Replacing The Control Module Or Daughter Board; 6.11 Cooling Fan; 6.11.1 Replacing The Cooling Fan - Bosch 800 series Service Manual

58300000202443_ARA_EN_C

6.10.1 Replacing the Control Module or Daughter Board

1. Remove power to the oven.
2. Remove the screws securing the right and left side trim pieces
to the cabinetry.
3. Carefully slide the oven out of the cutout ~16".
4. Locate the Service Guide (wire diagram) attached to the inside
of the access panel.
Figure 34 Control module access panel and Service Guide.
5. Remove the top front housing cover.
6. Disconnect the harnesses, labeling them as necessary.
7. Remove the control module or daughter board, dependent on
the attaching hardware, either screws or tab-locked, snap-in
standoffs. Release the tab-lock by squeezing the projecting
tabs and lifting the module.
8. Install the new control module or daughter board and reattach
all harnesses securely.
9. Restore power to the unit and test operation.
10. Replace the top front housing cover and the Service Guide.
11. Slide the unit back into the cutout and reinstall the side trim
pieces.
Whenever possible, conduct troubleshooting tests at the control
module, using the Service Guide as a reference.
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JANUARY 2018

6.11 Cooling Fan

The cooling fan is offered as a service assembly with noise-reducing
foam tape attached. Each cavity uses a 120VAC 50W max variable
speed fan with a normally closed HTC in series with it. If the fan stalls
or shorts out and the air in the fan area reaches 175°F/80°C, the HTC
will open and shut down the cooling fan. This action will cause the
control module to overheat, shut down, and return error code E302 or
E303. When the HTC detects a temperature of 150°F/65°C, it will
close and allow the fan to run.
To test the upper fan at the control module, check voltage across
X105 / Pin 3 and neutral. There is also a Cooling Fan Relay Test
available in Service mode. See the Service Mode section for details.
Figure 35 Cooling fan motor and HTC

6.11.1 Replacing the Cooling Fan

1. Remove power to the oven.
2. Remove the screws securing the right and left side trim pieces
to the cabinetry.
3. Carefully slide the oven out of the cutout to gain access to the
cooling fan from the rear of the unit.
4. Remove the rear oven housing.
5. Remove the top rear oven housing.
6. Remove the screws securing the outer fan housing cover, and
set aside.
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Service Manual for Bosch 800 Series Built-in Wall Ovens
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