I have a Bosch Cooker Hood Extractor model No DHE635B. The light bulb in it went a while back and today I switched on the controls for the fan and nothing happened. I found a Fuse plug in the nearby cupboard and changed it but still nothing.

Could someone please tell me how to find out if it's the circuit board or fan that needs replacing. Either way I think it's going to be very expensive to replace. I am not familar with these type of tasks so could someone explain in easy terminology please.

Angela, March 2012

ok angela what i was trying to eliminate was dismantling hood if prob was no supply or blown fuse (fuse is only 3amp and can blow when a bulb goes doesnt always mean elec fault) Also I meant the plug could be on top of the cupboard between it and the ceiling. Anyway I will proceed assuming the supply to the hood is ok:- 1) Isolate hood from elec supply if not sure which plug switch off fuse box (electricity kills!) 2) Open out door to full extent and remove filter cage 3) If you have glass hob under hood cover it with cloth and a board so if you drop anything you wont break glass also isolate it in case you accidently turn it on. 4) The door will come to a stop. Look inside hood you should see a red plastic stop on each side of quadrants (may be screws on later hoods) pull on stops (or remove screws)at same time pulling door slightly foward to override stops. 5) You may need two people door is heavy. Pull door further open untill it comes out of the hood completely .6)you will see the right side track that the hood quadrant came out of has a little button that the quadrant operates when it goes over it this is the micro switch the button could be jammed.Will be near back of track.7) If you cannot reach it up the track look inside hood there may be an inspection panel you can remove to reveal the switch on right side. (if this switch faulty or jammed nothing works it is usual prob with this hood) If not this would need elec meter and elec knowledge to diagnose. Best of luck.

Kenjo, March 2012

Thanks Kenjo - FD No is 8407. No cupboard above hood to locate another plug. Only one I can find is in the cupboard adajent to oven. Have tested it and appliances work fine. Have just found a socket on the back wall of cooker hob with an on/off switch (no plug goes in there) and there is a fuse cover. Shall change that fuse as well). Haven't bought a replacement bulb yet.

Angela, March 2012

Angela have got diag for your hood but before going into detail how to reach micro switch 1) are you sure the plug you found in cupboard is for the hood. Often plug for hood is on top of cupboard if there is one there check its fuse . 2) If you replace faulty bulb in hood does it work? 3) Plug something else into hood socket does that thing work ok. Let me know and if necessary I can guide you to the micro switch. kenjo

Kenjo, March 2012

Angela switch i mentioned will be visible only when your decor door is removed and is not the fan switches let me check your particular models parts diagram to give you more positive instructions can you give me the FD number (4 digits) Watch this space. Kenjo.

Kenjo, March 2012

Kenjo can't see this micro switch you have mentioned - flip what button? Do you mean the switches for the fan?

Angela, March 2012

If fuse is ok and you are checking the right plug the problem most likely is the micro switch jammed or faulty. It is situated on the right hand side of the hood. As the door opens the right hand slider operates it. Probably greased up you may be able to just flip the button a few times to release if not is accessible by little plastic trap door in casing - pull out elec plug first!

Kenjo, March 2012