Duplo 10874 engine lacks sound without app

Question

I have inherited this set which works perfectly apart from the fact that there is no sound from the engine. It clearly reads all the colours on the action bricks because, when used with the app, the little driver on the app blows the whistle and, through the app, I can hear the brakes and the water filling. This can't be heard without the app. Also, the noise on pushing the little green button to start up makes no sound although I believe it's supposed to. We've had it get taken apart to check but can't see anything wrong.

Has anyone else had this problem? Any help much appreciated.

Answer 1

I suggest you contact LEGO support. The set is recent enough for them to have spare parts. They'll happily replace the Push & Go component if you can demonstrate the part is defective and you own the set. To prove you own the set you'll need a code in the instruction booklet.

Answer 2

This solved the no sound problem, but mine also fails to read colors, only blue and red are detected.

Picture 1: I put an AA battery with wires to test the little speaker, did not make any sound, it was bad.

Picture 2: I had to trim the plastic base of the speaker to replace it with another one bigger which I removed from an old telephone.

Picture 3: Here can be seen the larger speaker substitute.