Nc2 interior light fuse location

  1. My model of MX-5 is: __nc2 2l sport ech
  2. I’m based near: __grantham
  3. I’m looking for technical help or recommendations on: __interior light FUSE location

Hi all,
I messed up!!!
while changing a broken interior light i shorted the connectors and presumably blew the fuse!

the key fob isn’t working, the stereo isn’t working, the engine management light is on and the DSC light is flashing.

tbh it seems like a lot for a single fuse!

so does anyone know which fuse box the interior light fuse is in, please?

I shall go to Halfords and buy some fuses in the morning and if I have to I will pull each fuse in turn until I find the blow one or ones!
however, it would be a big help if you guys could narrow things down for me

thanks all and merry Christmas
Thibor

nb, I’ve looked up the diagram and it looks like i might have blown 3 fuses!!

number 5 in the engine bay box and numbers 1 and 3 in the passenger comp box!]
is it really possible to blow multiple fuses by shorting the interior light?

(btw I will be renewing my membership in Jan, i didn’t do it last month due to Xmas and car expenses (new tyres)

It’s probably the ROOM fuse that you’ve blown, should be marked in the lid of the fuse box. I think it’s slightly raised compared to the others as well.

thanks, mate.
it was fuse 5 ROOM.

gotta say tho it seems odd to me that one fuse, the fuse for radio and interior light can affect so many systems.
it stopped the DSC, alarm, and central locking, and even put the check engine light on!
not to mention that when i turned the ignition on all the dials would go to full max for a moment before dropping back to their normal positions.

It’s the fuse that’s removed during shipping, stops battery drain over a long period of time.

2 Likes

it took a while for all the systems to come back btw!

the radio alarm and locking came back immediately.

the DSC didn’t stop flashing until I turned the ignition off and on after having driven about 1 mile
the engine light didn’t go off until after driving several miles and turning the ignition off and on

I’ve currently got a similar problem. The interior light bulb looks fine. I purchased a new one from MX5parts just to be sure and the light is still not working.

According to the fuse schematic (thanks for the link btw), room 15amp, is the one for interior lights, but the lights in my boot are still working fine.

Any suggestions would be much appreciated. Thank you.

Also, while I remember, any good suggestions for a replacement fuse kit?

If you invest in something like this Beizkna Digital Multimeter Voltmeter Battery Voltage Multi Tester AC DC Volt OHM Amp Current Meter Continuity Circuit Resistance Diode Ammeter Electrical Tester with Test Leads Backlight LCD Display : Amazon.co.uk: DIY & Tools then you can see if you have 12 volts at the bulb holder and also if the bulb and fuse are good. An invaluable cheap tool that will help with lots of things around the home and cars.
:heart:

You just reminded me that I do actually have a multimeter. It came with a soldering kit I bought off Amazon. I’ll go fish it out see what I find. Thanks!

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Top man, you are halfway to solving your issue. Good luck.
:heart:

fuse kit!
i looked for one and didn’t find any that were suitable as they all had some fuse types I didn’t need.
so I ended up buying a couple pr 3 of packs of 5 different amp-size fuses and made my own kit

So… I feel like were 50% there.

  1. Removed light bulb. - Continuity test - OK.
  2. Tested for 12v. None when doors are open and switch set to doors.
  3. Removed 15amp room fuse - Continuity test - OK.
  4. Removed 7.5amp illumination fuse - Continuity test - OK.
  5. Inspected light fitting. No signs of rust.
  6. Manipulated switch back and forth a couple times.
  7. Replaced bulb. Light now works with switch in the ON position.
  8. No 12v when doors are open and switch is set to Doors.

I don’t fully understand yet how the doors being open can activate the light switch.

When doors are open. The door open icon is light up on dash board console. When both doors close it goes away. So that’s a good sign?

Now I’m stumped as to where to look for the door open switch to activate the interior light to come on?

It sounds like it is a door switch problem. From the wiring diagram it looks like the actuation is to earth. I can not see where the switches are. Do you have those little plunger type switches? On the ND they are hidden away in the door but my Haynes NC manual does not reveal how they work on the earlier models.
I think you need someone higher up the ‘knowledge tree’ than me to guide you.
:heart:

I really appreciate the help. Yeah, I guess they are like rubber plungers. It’s like rubber covering the switch. https://www.mx5parts.co.uk/door-switch-interior-lamp-mk3-35-p-2281.html

So, just out of interest, do you know if the door open signal has anything to do with the interior light door open on/off switch?

Or are they two separate signals?

My guess is the switch on the interior light, as the door actuators are activating the “door open” dash warning lights. Check the voltage at the switch.

That is the good old fashioned way. Take the switch out and put the wire to ground and the light should come on.
The wiring diagrams I have do not show any connection. I can not see the dash illumination so have no idea how that works, sorry.#
:heart:

I have 12v when the interior light switch is set to ON.

When set to door, no voltage.

I was just looking online, seems like to get to the switch for the light I have to remove the surrounding trim. Is that right?

Tbf, the more I think about it. If the door switches are working then it’s pointing more towards the interior light itself. To have gone from not working at all, to now working when light switch is set to ON, is a result. :+1:

If the switch inside the light is a wonky, then more than likely that’s potentially where the problem is.

If I have to take the surrounding trim to get to the switch, would you say it’s probably wise to order a replacement interior light?

My understanding is that when you open the door the interior light does NOT come on.

According to the wiring diagram I have the switch does NOT switch the live, it works by completing the circuit to ground/earth.

It is strange that both doors do not operate the light as they show as being independent.

I would work the door switches vigorously manually to see if this ‘cleans’ the contacts. Then remove the interior light and clean all the contacts and connectors.

Without being there I can not offer any further help, sorry.
:heart:

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Correct.

That’s interesting. I’m very grateful for your research good man!

I’m just wondering where the door switches wire to? Is there a junction box for them that then branches off to map light and dash console to display the door open icon?
The door open icon on the console illuminates when the door is open, that looks part of the same circuit as the light. I’m only working with the Haynes manual wiring drawing.

That diagram suggests that there is a break in the wire from the Map Light to the junction with the wire from the Instrument Cluster to the Door Switch.

I would suspect the Map Light connection is not good, take it out and remove the wires and clean everything up.

NOTE WELL, the wire coming in is LIVE so either remove a fuse or disconnect the battery. If you put the switch to interior lamp position (you intimate that this lights the bulb) and remove the fuse you think is the correct one it will go out, if it stays on you are not ‘safe’.
:heart:

PS How is the Door Switch LH wired on the diagrams?