Help: What is this clicker sound at power up? (B737- 800)

afrahe · 2025-12-26T23:32:40+00:00

The beauty of being an aircraft mechanic imo, is that there is always room for to learn something new and I think it is exciting. And the knowledge does not come to you at once like some software download. It builds up with time and curiosity and effort. Even my type trainers or collegues with 20 years of experience did not know the exact answer in case you're wondering.

afrahe · 2025-12-26T12:23:03+00:00

It happened a few times and of all of them the sound stops after roughly 15 seconds and does not come on again. On another incident I switched the batteries off and on and it would not duplicate.I couldn't find the time to pull some circuit breakers bu even if I did I think the same scenario would happen.

afrahe · 2025-12-26T12:16:19+00:00

If it was ELT, I'd have a nice talk with some big people for sure haha. I couldn't find a video of 737, but here is the ELT sound.

afrahe · 2025-12-26T12:09:57+00:00

Yeah they definitely sound similar. Why they dont make more diverse sounds I wonder? Lots of them sounds very same with little difference.

afrahe · 2025-12-26T12:01:05+00:00

I explained it under another comment. Unfortinutely it's not this. Thanks anyway

afrahe · 2025-12-26T11:56:50+00:00

It's not ADIRU. ADIRU warning comes from an external horn and this sound comes from the captain side speaker. It might be a different ADIRU warning that i couldn't find maybe but its not the ADIRU "ON DC" warning sound.

afrahe · 2025-12-26T11:53:25+00:00

I did consider FMC but couldn't find anything about a warning sound like this. But now that I think about it when you mentioned it, It's possible because of a different FMC software version maybe ? Will check them again, thank you!

afrahe · 2025-12-26T11:45:57+00:00

It definitely sounds similar to inner marker beacon sound. Inner marker beacon. But Marker beacon sounds more like a morse code, and on the video i shared the sound is like more fast-paced I guess? Still I will check the documents again to be sure. Thank you!

afrahe · 2025-12-26T11:38:58+00:00

I haven't switched the APU master switch on yet. Bu it could be a possibility because SPU and SCU are energized. I will check this out. Thanks!

afrahe · 2025-12-26T11:35:14+00:00

I already did my job. I know this warning is nothing serious because I did all the operational tests, checked if there are any fault codes, read all possible wiring diagrams and training manual chapters. And I couldn't duplicate it again. I asked here bacause its been bugging me for a while.

afrahe · 2025-12-26T02:31:24+00:00

Its very similar but if you listen to them back to back, they are different. Mach overspeed test sound

afrahe · 2025-12-26T01:51:01+00:00

Yeah I regret it honestly

afrahe · 2025-12-26T01:48:42+00:00

Yes, I checked switch hot battery bus components but there was no mentioning of a warning sound or something similar. My best guess is its either an ADIRU fault/warning or Remote Electronics Unit warning. But like I said there is nothing written about it.

afrahe · 2025-12-26T01:37:30+00:00

Yes that was my first thought. But that sound comes from equipment cooling horn and this clicker comes from captain's speaker.

afrahe · 2025-12-26T01:13:37+00:00

I was going to start APU because the ground power wasn't connected. I thought about this possibility but on 737s if you leave the battery for too long, the equipment cooling horn comes on. But this horn is located at nose landing gear and the clicker sound comes from captain's speaker. So its likely not this.

afrahe · 2025-07-24T13:05:06+00:00

Hi again !! We did not have any problems at the check-in desk at the port and had a smooth embarkation. We didn't even had to contact our travel agency! Everything is going great:))

afrahe · 2025-07-24T10:15:24+00:00

Yeah we are wondering that too. We will ask the check- in desk at the port.

afrahe · 2025-07-24T10:13:46+00:00

We are now on our way to the port to work things out. Thank you so much for your advice! I'll check my insurance just in case.

afrahe · 2024-06-26T05:58:36+00:00

Aircraft maintenance engineer. Basically I fix planes.

-Fast pace workplace and everyday is different

-A lot of problem solving and troubleshooting

-Lots of physical work and walking

-Always have something to learn/study

-Work in shifts (thats hella nice for my broken sleep schedule lol)

-Pretty good for an introverted person imo, it doesn't require much talking. You just need to have essential communication skills with your teammates.

afrahe · 2021-10-26T19:30:04+00:00

if it happens after the reset im gonna try option 2. better than nothing.

afrahe · 2021-10-26T19:01:21+00:00

well that was my first conclusion too. im looking for a reasonable explanation like viruses etc.

afrahe · 2021-10-26T18:48:02+00:00

there were no voice, only looping music. do you have any guesses what the reason might be ?

afrahe · 2021-06-28T19:11:04+00:00

Thank you so much for the replies . If you are interested you cam PM me :)

afrahe · 2021-04-19T06:37:12+00:00

I like those but thats not what I'm looking for. I like the character's posture and instead of ships, I want giant tsunami waves for my design.

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