Dome light

FIFTY

Member
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3,100
The bulb in the overhead dome light appears to have blown... this is the one that is switched on/off by the button not the light that turns on when the doors open/close

Does anyone know the fitment and how to open the light up to replace the bulb?

I'm going to try to source a warm white LED replacement if I can to reduce the power draw on the battery when the engine is switched off.
 

hashluck

Member
Messages
1,515
It is in the handbook but you will see a little slot between the unit itself and the surrounding plastic trim. Use a slotted screwdriver in there and lever out gently. It can be easily unplugged. All bulbs will be visible. From memory the light you reference is standard bayonet type. The Map Light switch on these units is very unreliable so it may well be the unit at fault and not the bulb unfortunately. Replacements new and secondhand on ebay. If secondhand make sure they tested the map light before removal!
 

FIFTY

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3,100
Thanks hashluck! I forget the manual has some useful info in it. Hopefully it's just the lamp as it did work a little while ago. If I find some decent looking replacement LED lamps I'll post them up
 

Boomerang_GT

Member
Messages
202
I exchanged all with LEDs and am happy as can be :)
Before the light was hardly noticeable and if forgotten on would suck the battery empty over night.
Now really seeing something with the bright light and could leave it on for days.
 

FIFTY

Member
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3,100
Removed the dome light the filament on the reading light seems to be ok but I'll replace it anyway and see what happens... Guess there is a chance the switch is broken... possibly both of them as "button P" is meant to manually switch the central festoon lamp which switches on when the doors open/close... button P does nothing!

Screenshot_2017-12-04-20-47-14.jpg

Can the switches be repaired? I'm guessing this happens because they are out of the fiat parts bin from the turn of the millennium and they spent less than £0.0001/each on them
 

FIFTY

Member
Messages
3,100
If any it would be the dash ECU. The reading light definitely used to work as I left the light on once and I drained the battery

75-100 for a used one that will probably break again. They must have installed these on the ceilings of some crappy fiats, could there be a cheaper alternative part floating around out there? I'll do some digging

Edit: no luck finding an alternative but I managed to pry off one of the buttons and there is a microswitch underneath that can probably be replaced for pennies
 

FIFTY

Member
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3,100
I have fixed the switch that controls the central 36mm festoon bulb, I noticed there was some corrosion on the solders behind the switch and the contacts had raised slightly as a result (circled in red below)

I cleaned off the corrosion with a copper brush and pushed down on the contacts with my thumb, connected it back up and the switch works!

20171205_104249.jpg

Still no reading light, will order a new bulb and see what happens... but at least I have a light at the front I can control without opening the doors :)
 
Messages
342
@FIFTY - reviving this thread as I'm having similar issues, but slightly different, so amplifying this post for future dome light troubleshooters.
Symptoms: main light would turn on/off only with passenger door opening/closing, not driver door, though all other driver door functions are working. Neither switch had any effect, and the switch illumination was not working.
Before I found your thread, I pulled the unit, noted the two main bulbs were both intact. Used contact cleaner (alcohol) on the switch areas. Reinstalled, and now the main light works with the switch, but the smaller map light does not. And the switch illumination 3W bulb requires replacement.

Thank you for tracing out the connectors - saved me some multimeter time.

* did you end up getting the two main bulbs replaced with LEDs? If so, could you please share the bulb code for them?

I don't have a wire brush around, but will pick one up tomorrow and give your method a try. I must say, the feel of those switches certainly leaves much to be desired!
 

FIFTY

Member
Messages
3,100
@todd.the.submariner I used these COB LED lamps... but i vaguely remember 36mm being too small and I had to order 39mm... Although I would double check that as it was a few years ago and my memory is a touch vague so definitely check the length of that torpedo shaped lamp before ordering

weiXuan Pack of 4 LED Car Festoon Dome Light 27mm/31mm/36mm/39mm/41mm 12V 360 Degree COB Filament Lamp Warm White 3000K for Car Reading Bulbs,Interior Lights,License Plate light (39mm, Warm White) https://www.amazon.co.uk/dp/B06X9LX...abc_RC5S9VRPAGJC8J9QHB45?_encoding=UTF8&psc=1

They work really well and fit into the vanity lights in the rear of the cabin. They are a nice warm white colour which matches the old lamps (nothing worse than when people but really white or blue light to replace halogens)... going to have to order another one for my trunk light as that is still halogen.

Ps. To clean the contacts I used a brass wire brush
 
Messages
342
@todd.the.submariner I used these COB LED lamps... but i vaguely remember 36mm being too small and I had to order 39mm... Although I would double check that as it was a few years ago and my memory is a touch vague so definitely check the length of that torpedo shaped lamp before ordering

weiXuan Pack of 4 LED Car Festoon Dome Light 27mm/31mm/36mm/39mm/41mm 12V 360 Degree COB Filament Lamp Warm White 3000K for Car Reading Bulbs,Interior Lights,License Plate light (39mm, Warm White) https://www.amazon.co.uk/dp/B06X9LX...abc_RC5S9VRPAGJC8J9QHB45?_encoding=UTF8&psc=1

They work really well and fit into the vanity lights in the rear of the cabin. They are a nice warm white colour which matches the old lamps (nothing worse than when people but really white or blue light to replace halogens)... going to have to order another one for my trunk light as that is still halogen.

Ps. To clean the contacts I used a brass wire brush
Got the brush, cleaned it all up, and no change for the map light, but the main light works. There are problems that must be external to the dome light assembly itself.
  • no map light under any conditions. Probably the switch, the bulb is intact. Will troubleshoot after sorting out the main light.
  • main dome light works with switch, and all interior lights work when the passenger door is opened. But, no lights come on when the driver's door is opened - all other door related functions work, such as the window drop, transmission disengage, so am wondering if there are multiple microswitches for door position. Some research to do here, but if you happen to know, do tell!
  • switch illumination bulb burnt out - replacement on order.

LED bulb on order for dome light replacement, just because. Will post what the final correct size is once I get it installed.