I have just had this fault happen in a AEG built in MWO. The cause is microwave leakage from the waveguide, as a result of the rivets securing it together being loose. The RF energy causes the control board to reset, or throw up error code F134.

At last a comprehensive rationale for this fault. looks like a poor design . I ditched mine in the end !

Thank you very much for the solution. Have recently changed everything inside the microwave without it helping. I drilled out the rivets that were loose and put in body screws. The microwave was like new afterwards.

Hello everyone,
same problem here, with an AEG KR8403101M microwave oven.
The official AEG repair service substituted initially the main board, without any success. Response: microwave leakage, unrepairable.
Now: I'm looking at the rivets but cannot understand if there's anyone of them loose, the ideal view it's probably not from inside the oven but from the external, upper part. Tried to disassemble but it's quite a mess; as I've read a user sustituted that rivets, how did it reach the other side of the rivets?
Do I have to unmount *everything* from the top to toggle the upper cover from the oven?
Thanks for any advice,
Matt

Hi Matt. Never pulled mine apart, so can't give any clue on the difficulty. You'd need to remove all the stuff above the waveguide to repair it though. Good luck!

Having stripped mine out and ditched the casing Ive got a box of component parts available at next to nothing prices.
Power board, Display board, Magnetron, Transformer, Capacitor etc
Anyone interested in a job lot, message me directly graham@gbsirocco.co.uk

Graham