interior light wiring on "T" bar lamp.

[Mark Shutt]

hi all, I've read just about every topic on interior light wiring and I'm still baffled as to how on earth all the lamps ever worked together!! basically I have come to the conclusion that the T bar lamp black wire (earth) should be permanent live to make everything work hunky dory. mine is a late mk2 and have gone over the correct schematics that are hard to find but my car makes no sense! I have puddle lights and foot well lamps working great but the T bar lamp cannot function as is. is there a +ve feed anywhere near the B posts I can use?

[DJT]

Hopefully our resident interior wiring expert Julian will be along soon.......

[Mark Shutt]

It's mad, I just don't get how it ever worked, I've cleaned the switch out and checked the wiring over many times! If I leave the black earth disconnected all other lamps work OK, If I connect it up then they work permanently until I press switch then they go off and foot well lamps come on!

all work OK if I run an live feed from cigar lighter...

[Omen]

I had a problem where the T bar lights, puddle lights worked, but footwell ones did not. The black wire to the T bar lights is the feed, not the earth. Feed then goes thru the bulb to the footwell. A PO had cut the secondary feed to the footwell lights, soon as I figured that and supplied a feed, (and replaced a bulb!) it all works fine, doors open or the switch in centre console. Have you figured that only one T bar bulb lights up per door and the corresponding footwell to the open door? Only time all four come on is, both doors open or turning them on with the console switch ?
If you search in forum, for interior lights you should find Julian's diagrams and explanation which explain it all.

[Mark Shutt]

the black wire in mine is earth, I would like to know where this is connected, it should be +VE feed..

yes, I know the T bar is split and one bulb per door opening (or both from switch)

[Omen]

At the risk of teaching you suck eggs (again!!) the black feed rises thru the B post. It maybe your PO cut it somewhere and earthed it, as not being able to see passed black=earth. If you traced it back, may find the cut and be able to re-connect ??

[Mark Shutt]

this is what I'd like to know, where it goes to. I wonder why anyone would change it from + to -?

[jleyton]

Thanks Dave and Damian,

I'm out in France on Hols at the moment and only have my phone.

if Mark does a search I hope he'll find the post I did earlier this year with a title something like 'interior lights - an explanation'

Mark, if you're still baffled I'll be back in Uk after the weekend and happy to advise - PM me then if you're still stuck .

Good luck

Cheers

Julian

[Mark Shutt]

Thanks Dave,

I'm out in France on Hols at the moment and only have my phone.

if Mark does a search I hope he'll find the post I did earlier this year with a title something like 'interior lights - an explanation'


Good luck

Cheers

Julian

thanks Julian, yes I have read and studied that post and diagrams! it all comes down to the black wire and why it is earthed in my car. now I have the task of following it's route back to where it connects (footwell?), my 1st attempt at B post removal was a failed mission, it wouldn't budge

[jleyton]

Hi Mark

it comes along in the loom on the right hand sill. I seem to remember that it changes colour to black there, but not sure.

one of the many reasons I don't glue my sill carpet down !

Good luck and, as mentioned above, PMme when I'm back if I can help - fingers failing on phone !!

Cheers

Julian

[jleyton]

Ps it's probably been altered cos a PO didn't understand it- quite common and with no proper wiring diagram and a. BLACK FEED. wire that's not surprising !!

[V Mad]

I know they used a black feed on the interiror light switch, but I dont recall the t-bar lamp being wired that way. But there was a change there from Mk1 to Mk2 so maybe they did?

[Mark Shutt]

well I've spent the last hour and a half on my back under the footwell/dash trying to find where this black wire goes and still non the wiser! on the plus side I found the original stereo feed so will correct that at a later date so the stereo turns on with 1st click of key

one question though, how the hell do I remove the B post trim? I took the seat belt bolt out but the whole thing is solid!! I may just end up running a new feed up to the lamp and be done with it, it annoys me it won't be correct but I'm spending too much time trying to fix the thing

Mark.

[Bob Heritage]

B post trim just clips in.

[Mark Shutt]

B post trim just clips in.

tried pulling on it but it wouldn't budge!