Hi, my interior light on MK2 focus went weeks back, mechanic gave me a spare bulb when I had mot last week. I replaced bulb but still not working still .. I check fusebox today fuse 104 I think. It doesn't appear to be blown ...any ideas? I think maybe button mechanism has gone? Any ideas?

Mj thanks!

Measure the fuse before saying it is all right. Check the bulb likewise. The light works in several different modes. Read your handbook and ensure that you haven't switched it off by mistake. Does it work, for instance if the key fob is used, or a door is opened? do any other interior lights work?

Measure it? Sorry I've never really looked at fuse in car before but it's not broken as some are on Google ..? I don't think it's off no... Jiggled button around it's a dodgy button but bulbs new... It was working a few months back...then stopped made me think it's bulb...so tried new bulb and nothing?  No other interior light

Head/tail comprehension mismatch error.

1 hour ago, mjj said:

MK2 focus went weeks back, mechanic gave me a spare bulb when I had mot last week. I replaced bulb but still not working still .. I check fusebox today fuse 104

I'm a little confused. Your profile says the car is a 2011, but only Focus built up to (but not including) 2010 had a fuse box with fuse 104 for the interior lights. Vehicles built 2010 onwards had the interior light controlled by the Body Control Module.

If you have a multimeter, see if you have 12v between the 2 x prongs where the bulb is pushed in, remembering to have door open or switch to 'on'...

45 minutes ago, unofix said:

I'm a little confused. Your profile says the car is a 2011, but only Focus built up to (but not including) 2010 had a fuse box with fuse 104 for the interior lights. Vehicles built 2010 onwards had the interior light controlled by the Body Control Module.

I must got profile wrong when I registered sorry my error...2008 ford.. in my handbook said fuse 104. But looking at it appears fuse ok but will try checking it...

35 minutes ago, mjj said:

must got profile wrong when I registered sorry my error...2008 ford..

Ah!!!

That makes a lot more sense now 😀

You can easily edit your profile and correct the year to 2008 which would be a good idea to avoid future confusion 👍

18 hours ago, unofix said:

Ah!!!

That makes a lot more sense now 😀

You can easily edit your profile and correct the year to 2008 which would be a good idea to avoid future confusion 👍

Ok will do. Would u advise getting fusebox checked or just trying a new fuse first? I thought fuse looked ok? Did u see pic?

17 minutes ago, mjj said:

Ok will do. Would u advise getting fusebox checked or just trying a new fuse first? I thought fuse looked ok? Did u see pic?

I did advise a few posts ago to see if you were getting electricity to the actual bulb holder, a very simple test - if not, you could certainly investigate the fuse further despite it looking OK! The same tool, a multimeter, will test both...

19 hours ago, unofix said:

Ah!!!

That makes a lot more sense now 😀

You can easily edit your profile and correct the year to 2008 which would be a good idea to avoid future confusion 👍

Ok will do. Going to buy a multimeter thanks stephen

4 minutes ago, mjj said:

Ok will do. Going to buy a multimeter thanks stephen

A multimeter will test 100s of things, but if you only ever use it for testing if a battery is good/bad, worth it's weight in gold...

...And having bought one

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwiRpZ_J8O_8AhUDgFwKHSTZBiYQFnoECA0QAw&url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3Dts0EVc9vXcs&usg=AOvVaw0jrI8XOFMff0aOUDU1Ht1I

16 minutes ago, StephenFord said:

A multimeter will test 100s of things, but if you only ever use it for testing if a battery is good/bad, worth it's weight in gold...

A multimeter in isolation will only tell you the no load voltage, not how much energy is stored in the battery or the resistance between the battery and where you are testing - you need to put a load on the battery, or wereever you are testing, and check voltage drop from no load voltage.  A test lamp can be more use on 12V systems.

7 minutes ago, Paulkp said:

A multimeter in isolation will only tell you the no load voltage... 

For most, when their key fob stops working, or their torch fails to light with an AA 1.5v in it, this is perfectly adequate. If you need the kind of diagnostics you describe, the person already with a multimeter will know... and, a continuity test will certainly expose a blown fuse.

39 minutes ago, StephenFord said:

A multimeter will test 100s of things, but if you only ever use it for testing if a battery is good/bad, worth it's weight in gold...

A multimeter in isolation will only tell you the no load voltage, not how much energy is stored in the battery or the resistance between the battery and where you are testing - you need to put a load on the battery, or wereever you are testing, and check voltage drop from no load voltage.  A test lamp can be more use on 12V systems.

I'm not sure why that post has an echo !

Agreed Stephen.

Back to the interior light......

The GEM controls the interior lights.  If all the other interior lights work, including vanity and map lights, then the fuse/GEM is probably OK.  If just one interior light fails, it can only be the bulb, bulb holder or rhe switch controlling that light ?

59 minutes ago, Paulkp said:

A multimeter in isolation will only tell you the no load voltage, not how much energy is stored in the battery or the resistance between the battery and where you are testing - you need to put a load on the battery, or wereever you are testing, and check voltage drop from no load voltage.  A test lamp can be more use on 12V systems.

A multimeter will tell you the resistance between the battery and the circuit under test.

42 minutes ago, Paulkp said:

I'm not sure why that post has an echo !

Agreed Stephen.

Back to the interior light......

The GEM controls the interior lights.  If all the other interior lights work, including vanity and map lights, then the fuse/GEM is probably OK.  If just one interior light fails, it can only be the bulb, bulb holder or rhe switch controlling that light ?

Or the wiring to or from the power to the switch or bulb or bulbholder or return.

Thanks all!! Will get .multimeter and get started

 

Good Luck - Keep us posted !

16 hours ago, Paulkp said:

A multimeter in isolation will only tell you the no load voltage, not how much energy is stored in the battery

Cue @unofixand his SOC table . . .

......and here it is 🤣

For a good battery, yes, but I have one that holds 12.7 after eight hours and yet will not crank an engine. Seems the SG is very low and yet both smart chargers think it to be all right.