How to check Dome light switch?

[MisterCruiser]

So 1 of my 2 dome lights works intermittently, but mostly doesn't work. It;s not the bulb, it works sometimes, I've switched them over and still doesn't work. There's good contact made with the bulb with the fitting and holder.
I think it's the switch. Can anyone tell me how to dismantle the switch in the pic and check it? It's the one marked with the white paint mark, but they're both the same anyways.

I tried probing various bit of the unit with my multimeter set to continuity with the switch pressed / unpressed etc,,, but couldn't find anything of note. Is there a check I can do like this without dismantling the switch itself?

What is the exact type of bulbs these are? The mini bayonet type fitment, I don't see them on Halfords? I'd like to fit 2 new ones so I don't have to root at them for a long time again.

Also, can anyone recommend a couple of little lights I could add to the footwells to brighten it all up a bit, not too pright, just a subtle light down there as the interior lighting can be a bit lacking.

 

[Tractionman]

MisterCruiser, check your courtesy switches in the door shuts for operation, Ive had intermittant problems before with these sticking, which has resulted in flickering or non operation of lights.

 

[MisterCruiser]

Good thinking, I checked them and they work, ie: they aren't stuck in.

I put new bulbs into the dome unit today to rule out a dodgey bulbs, and the same one still didn't light up. I connected it directly to my battery again and it's a dodgy switch, it lit up intermittently and when it was lit when I'd touch the switch lightly it'd go out. But when it was fitted in the cruiser no amount of messing at the switch would turn it on.

I'm not sure how to dismantle the switch without breaking it? Can you even buy the switches individually? I might fit a new Led unit altogether.

If anyone knows how to dismantle the switch I'd appreciate the tip.

 

[Towpack]

They look like latching push-to-make/push-to-break switches which aren't really designed to be opened up and repaired although it can be done. It's probably just burnt and/or oxidised contacts which could possibly be cleaned up with some fine emery and switch cleaner, assuming the detent spring isn't broken. You could try squirting some Servisol switch cleaner (or similar) inside the switch body.

 

[MisterCruiser]

I didn't want to break the unit / switch trying to open it, might give it a go again sometime when I've more time / patience to investigate it. The light out of it isn't great anyway so I just fitted a new Led unit I had floating around me shed. Biggest gripe I have with any modern electrical stuff is the ultra thin wiring that comes with them, I had to fold / triple up the wire in order to get it to a half decent size to fit into my smaller than standard spade crimp connector. I didn't have to alter the oem loom, my 2 little spades plugged into the Toyota plug.

I think I'll have to trim a little bit of the head liner away to compensate for the new bigger light, but that shouldn't matter too much.

 

[Steve H]

Hi. I have had the same problem but on a window switch on my sons Picanto. I got it working by filling the switch with brake cleaner and operating it on and off a few times to clean the carbon off of the contacts inside. Got it working but very slowly at first but is now working as new. Your switch could have the same problem. Another way is to use WD40 after the brake cleaner to free up anything sticking inside.
To light up your footwells, try looking for Prism LED stick on door handle lights. Halford's used to sell them, along with pinhole leds in packs of four. You fit the pinholes by drilling a 6mm hole and fit a small plastic holder, then push the LED into this to hold it in place. I did have some in blue somewhere. I will look for them and try and get you a photo.

 

[DH.120]

Wouldn’t recommend using standard WD40 as it will “attract” dust and dirt- it’ll probably work short term but in the end you’ll be back to the same issue. Would recommend using a contact cleaner as this is quick drying and you will not have the issue, can be got quite cheaply at most auto stores or Screwfix Had the same issue before on motorbike turn signal switches, and this has always fixed the problem.