Interior lights dim

[Jenny2020]

Can anyone help me please?
Suddenly all my factory fitted interior lights are dim.
If I put the ignition on I get usual full brightness, off and all lights dim again
I’ve replaced the battery, still the same dimness. In these dark evenings I need some light.

[gilly99]

Probably bad earth, or loose connection someplace.....also do you have a high parasitic battery drain? Bit extreme to replace battery for this type of fault, was the battery dead? Might take some finding!!

[Jenny2020]

Thanks Gilly,
Yes it was old and needed replacement.
Sorry I don’t understand a ‘high parasitic battery drain’
Looks like I’ll need to get an auto electrician then?
Thanks for replying tho
Jenny

[g8dhe]

Do you have a leisure battery fitted that is running the lights ? If so it might just be that battery that is low in charge, when you turn the Ignition on and run the engine then the alternator charges the batteries both starter and leisure together and this might be why the lights then come on brighter.
There are other possibilities, like has there been any servicing or work done on the vehicle at all ?

[Jenny2020]

Hi g8dhe!
Thanks so much for taking time to reply.
I thought that my leisure battery was only running the conversion fitted lights but I may be wrong. Is there a way of checking if that’s the case? The conversion lights seem ok it’s only the factory fitted ones that are dim. However I take your point.
I’ve checked the leisure battery and it’s showing green, but it Is a little old.
No, no servicing or other work done recently- this just happened out of the blue…..

[g8dhe]

Simplest way to check is disconnect the LB and see if the lights go off when the engine isn't running. Normally the most common (but not the only way) is to add what is called a Swap Loom, its 4-wires plugged into the internal fuse box down by the drivers knee, which are wired off to another fuse box added to the leisure battery this means that you don't flatten the starter battery when running the radio, both sets of blinds or the internal cabin lights (4 circuits).

[Jenny2020]

Oh thank you so much.
I think you may well be right. Why didn’t I think of that?
I was just so sure that the cabin lights remained factory fitted after conversion.
LB on charge now but may be dying.
Anyway I think this is probably above me and I’ll try and find an auto electrician….
At least you’ve given me some idea of what may be the problem.
Can’t thank you enough!

[Sally'sbongo]

Also your new conversion lights are probably LED and won't need as much power.

[Jenny2020]

Indeed. Thank you.