Bosch oven hbl755auc

The issue you're experiencing with your Bosch convection microwave not heating in convection mode could be caused by a few different things. Here are a few things to check:

1. Check the settings: Make sure that the microwave is set to convection mode and that the temperature and time settings are correct.
2. Check the element: The bottom heating element is responsible for providing heat during convection mode. Make sure that the element is not damaged or burnt out. You can visually inspect it, if it is damaged it will need to be replaced.
3. Check the fan: The fan is responsible for circulating hot air during convection mode. Make sure that the fan is not blocked or damaged. If it is, it will need to be replaced.
4. Check the control board: The control board is responsible for controlling the functions of the microwave. A malfunctioning control board could prevent the microwave from heating in convection mode.
5. Check for a blown thermal fuse: A thermal fuse is a safety device that cuts off power to the oven if it overheats. If the thermal fuse is blown, it will need to be replaced.
6. Check for a blown thermal cut-off: A thermal cut-off is a device that cuts off power to the oven if it overheats. If the thermal cut-off is blown, it will need to be replaced.

The oven has internal fan at back of oven encircling the element that should get reshot when stat turned up high. Also there is cooling fan under lid to keep the wiring area cool.This should stay on for around ten - fifteen minutes after cooking finished. David "The Famous Forry"

When that fan starts up the air pushes against an air switch and that tells the board the fan is blowing. The stove uses a DAC system that relies on switchs to confirm the operations of the fan. the DAC control uses signal voltage to detect switch function. The air switches must physically close by air movement from the cooling blowers before the oven proceeds into a bake or broil mode. Reason being f the cooling motor does not function and the oven goes into a bake or broil mode, the oven will overheat and could damage the fancy smancy over engineered piece of garbage electronic components. My opinion. This is not for the DIY unless you are a TV repairman.

If you need further help, reach me via phone at https://www.6ya.com/expert/dan_73bbd84fe1d95b61

Hi.
If it is a fan assisted oven, and it is the fan oven you are referring to, then I would suspect the fan element to be faulty.
Assuming you are in the U/K, this should be located at the rear of the oven compartment behind a removeable cover.
Alternatively, it is possible that the selector switch could be faulty, but I would check all elements first.

I found a users manual for Bosch wall ovens at Retrevo.com

http://www.retrevo.com/s/Bosch-HBL755AUC-Ovens-review-manual/id/925ci470/t/1-2/

Hi,

Do you see any Error Message on the Display?

If not, then it should not be a Concern. More often this could be Thermal Fuse on the Back of the Unit ( On Most Models ) will stop the Broil and Bake from Turning ON. You would just start a bake cycle and the temperature will sit at 100 and something degrees and never raise.appliance.

Let me know, once you check the same.

Hope i helped you.

Thanks for using ' Fixya ' and have a nice day!!

Print the following infore for future ref if you wish. How it works is simple tage a look at it in Motion
Component Test Procedure Results
Electronic
range control
F1−1 –Upper Oven >650°F with door unlocked.............................
F1−2 –Lower Oven >650°F with door unlocked.............................
F1−3 –Upper Oven >950°F with door locked.................................
F1−4 –Lower Oven >950°F with door locked.................................
F1−7 –Membrane switch is not responding ...................................
F3−1 –Upper sensor is shorted at (< 100 ω) or
open at (>5 K ω) ...............................................................
F3−2 –Lower sensor is shorted at (< 100 ω) or
open at (>5 K ω) ...............................................................
Check actual upper oven temperature,
if > 650°F check sensor.
Check actual lower oven temperature,
if > 650°F check sensor.
Check actual upper oven temperature,
if > 950°F check sensor.
Check actual lower oven temperature,
if > 950°F check sensor.
Check membrane switch for connection or damage.
Check upper sensor, harness, and connections
Check upper sensor, harness, and connections
Engineering
Test Mode
Press BAKE pad.
Enter 100°F using the number pads.
Immediately push and hold BAKE pad for appropriate oven
approximately 3 seconds.
This mode can also be entered by pressing the hidden pad
for 3 second located to the left of the lower oven light pad.
Used to view the actual oven temperature for both ovens at all
times, even when an oven function is active.
This mode will also display the current fault code for 5
seconds in the time digits.
Fault codes
accessed
through
Engineering
Test Mode
F0−0 –No fault .................................................................
F1−5 –Upper hardware failure within control ....................
F1−6 –Lower hardware failure within control.....................
F1−8 –Shorted key in membrane switch ..........................
F1−9 –Internal communication errors within control .........
F1−A –Upper latch switches ............................................
F1−B –Lower latch switches.............................................
F1−C –Upper door switch.................................................
F1−D –Lower door switch.................................................
F1−E –Sensor input not calibrated ...................................
F1−H –EEPROM error .....................................................
F1−L –Temp in ovens are the same for long period .........
F1−N –Internal voltage on control not working .................
F9−1 –Upper lock switch is not correct.............................
F9−2 –Upper unlock switch is not correct.........................
F9−3 –Control does not see upper door lock....................
F9−4 –Lower lock switch is not correct.............................
F9−5 –Lower unlock switch is not correct.........................
F9−6 – Control does not see lower door lock ...................
EE –Control cannot read E-PROM. Unit will shut down.
Default from factory
Replace control
Replace control
Check membrane connection
Replace control
Check latch wire harness
Check latch wire harness
Check lock wire harness
Check lock wire harness
Verify sensor is operating properly
Replace control
Verify sensor is operating properly
Replace control
Check lock wire harness, and lock switch
Check lock wire harness, and lock switch
Check lock wire harness, and lock switch
Check lock wire harness, and lock switch
Check lock wire harness, and lock switch
Check lock wire harness, and lock switch
Disconnect power for 60 seconds. If EE reappears, replace ERC
Test Mode This mode must be activated within the first 5 minutes of
power up.
Press BROIL and CANCEL pad for approximately 3 seconds.
If oven temperature is greater than 400°F, the Test Mode
cannot be activated or will abort if active.
Press and hold individual pads for 4 seconds to activate.
Display will have dashes in all segments to indicate the mode is
active.
Upper Bake: Energizes upper bake element
Lower Bake: Energizes lower bake element
Upper Broil: Energizes upper broil element
Convection Bake: Energizes convection fan
Upper Oven Light: Energizes upper oven light
Lower Oven Light: Energizes lower oven light
Upper Clean: Energizes upper motorized door lock
Lower Clean: Energizes lower motorized door lock
Stop Time: Energizes Beeper
Cook Time: Displays error codes
Timer 1: Energizes ROM version
Timer 2: Energizes EEPROM version
Keep Warm: Cooling Fan
Clock: All display segments light
If functions do not perform as specified, replace ERC
Oven
temperature
adjustment
Push BAKE pad.
Enter 550°F using the number pads.
Immediately push and hold BAKE pad for appropriate oven
approximately 3 seconds.
To decrease or increase oven temperature. Push AUTO SET
pad until negative or positive numbers appear. Oven can be
adjusted from -35° to +35° (-37.2° to + 1.6° C) in 5° F (2.7° C).
To avoid over adjusting oven move temperature -5° each time.
Push OVEN CANCEL button.

If you need further help, reach me via phone at https://www.6ya.com/expert/dan_73bbd84fe1d95b61

Dear customer,
i recommend u to try the following routine to sort out this problem

Check timer and clock settings

Reseat the element

Test the element

Test the element connectors

Test the oven temperature control

Test the oven selector control

Recalibrate the temperature control

hope u find this useful. thank you.

This sounds like a control panel issue, you may have to replace it, about $300.00