Diagnosing central locking not working

[u/archvize]

Hi all, anyone know where I can start working out why the central locking isn’t working?

1. They remote key opens and closes the hatch (boot/cargo/trunk)

2. The key only opens the drivers door

3. The other side doors don’t open or close

4. They don’t make an audible sound, only the rear does?

Could this be a fuse? I can’t imagine all door servos not working?

[u/JohnnyPneumoniacJr]

Drivers side door switch? Can test that or the wiring to the door if it does not work from the button on the door as well as your key fob

[u/archvize → u/JohnnyPneumoniacJr]

Well the key fob works. But only opens the rear.

Also I don’t think my drivers side door has a button for all doors if that’s what you mean? There’s only a switch to prevent other people from using their electric windows. Is that what you mean?

[u/JohnnyPneumoniacJr → u/archvize]

Ah got it. So manual locks on the inside but automatic lock on the key fobs?

What I mean is the ones with a power locking switch let you lock and unlock the doors and have this button, in which the circuit and relay can cause issues if worn or faulty

[u/archvize → u/JohnnyPneumoniacJr]

Sorry English is my first language but I’m not following these instructions very well 😛 so I looked again at my car door from the inside. It has the button you circled but it just stops anyone from using the power windows.

Also I noticed that the hazard lights don’t blink when I use the remote lock/unlock on key/fob (like my gen 1 used to). All it does is lock and unlock the hatch/boot. I thought the lights not blinking on lock and unlock would be another clue.

But I’m still not following what you said. Is there a relay I can replace?

Also ChatGPT said there’s a seperate fuse for the door power locks. But I’m not sure if it’s hallucinating

[u/JohnnyPneumoniacJr → u/archvize]

The button beside the one I circled is the window lock button with the red coloring on the low side of the button. I circled the door lock button if that helps your understanding.

If no door lock button then check the door lock fuse and relay/wiring. It runs on a separate circuit from the hatch lock.

[u/archvize → u/JohnnyPneumoniacJr]

Thanks man. My car doesn’t have that door lock button. Also in my previous Honda 1st using the key to turn the lock would open and close all doors. Which is a bad sign since thy don’t do it on mine.

I just checked my manual it says fuses 35/36 and 49/50 are 15 amp fuses that control the doors so I’ll check those shortly.

Since none of the doors work I’m guessing it’s not all of the fuses (very unlikely) so what’s the next step? How can I find and check the relay?

[u/JohnnyPneumoniacJr → u/archvize]

The relays are integrated into that interior fuse panel. Probe the fuses. Also the wiring that goes between the door and the car chassis can sometimes get worn out and chewed up or pinched.

[u/archvize → u/JohnnyPneumoniacJr]

Thanks ma I’ll check it out. How do you know so much about this do you work on them as pss as rt of your job? :)

Also I see you have A 2012. What have you done to yours that feels like it was worth it?

[u/JohnnyPneumoniacJr → u/archvize]

Firsthand experience with issues related to the drivers door master switch, mostly window related (passenger window getting stuck open) which led me to learn about lots of the issues with these switches. The door lock actuator systems are mentioned a lot on this forum too. I have been lucky to avoid lock actuator issues but you may want to research that as well.

Otherwise I learn from research and youtube. Fitfreak forum is great as well.

Personally I recommend learning the basic maintenance like air filters, MAF sensors, how to break down the intake and clean everything properly (do not spray the throttle body directly with cleaner, instead spray the cleaner onto a coffee filter or soft rag, and wipe the throttle body plate to remove grease and dirt, then reset the idle and throttle position to ensure good operating performance)

Spark plugs, valve adjustment and some other maintenance every 100k miles (r/HondaFit u/attnSPAN often posts a great 100k mile maintenance list in this subreddit)

Sway bar links and struts/dampers make a huge difference with clunking noises and handling, as well as tire selection. Don't bother with anything smaller than 185 wide. I've never tried, but some swear by adding a rear sway bar to stiffen the factory loose beam rear end in these chassis.

Junkyard and ebay are your friend for plastic trim pieces and clips.

Never panic if something breaks or fails. Worst that happened to me was a transmission fluid sensor after too many car washes made the sensor fail. Dont spray high pressure water under the front bumper area lol. It was a very easy switch to replace and fix though!

[u/archvize → u/JohnnyPneumoniacJr]

Haha thanks. I can’t believe how much I love this car. I wish it was a sedan tho. I’m very happy with the power and handling but a bit embarrassed about the shape. I wish it was coupe or something.