610 Interior light: Erm, don't geddit

the light that goes on when you open the door works fine, but the interior map light has never worked, so today in my wisdom i finally decided to take the unit out and find out why. In there i found three terminals, and only two wires connected to them, one red and one orange. That obviously leaves one of the terminals blank. I can't find any more wires hidden away anywhere. All the contacts look good and both bulbs are also checked and working.

I tried to trace the circuit and work out how it functions but... it's made by Alpine so obviously is was built in the most complicated and strange way imaginable. That and wiring was never my strongest subject.

Anyone 'shed some light on this?'- see what i did there

Alex

In there i found three terminals, and only two wires connected to them, one red and one orange. That obviously leaves one of the terminals blank.

I can't find any more wires hidden away anywhere.

Hi Alex
I think you will find that there is only two terminals used, as you say one Red. and one Orange, but if it is the same as the GTA, there will also be a Black wire (Earth) which on the GTA is located under one of the two fixing bolts. Does the manual switch work
If you go "Some Electrics No Worky" under General Discussion, Oct 13th. you will find an exlpanation of the workings for the Interior light I posted in reply to another post.
John

[mettersl]

Hi Alex,
I have just checked the A610 wiring manual and its the same as a GTA as John described.
There should be three wires-
1) Red to the fuse (no 3 in the fuse box) - goes to pin 3 on the lamp- cable number 52.
2) Black to pin 2 on the lamp,cable number 633, goes to a connector (4) to join with the passenger courtesy light earth and then goes to Earth M10 on the left door pillar- its down in the foot well behind the carpet. (I have found right and left are often the wrong way around on RHD A610 wiring diagrams). There is also an earth just behind the light- so you may be able to get a connection there, if you cannot find the original cable.
3) Pin 4 on the light should be orange , cable 284, it goes to the central accessories unit under the passengers feet.

Good luck, Lee

Following on from what Lee says, yes you have lost the earth to the lamp unit. It works like this:- Each lamp has 12v permanently on one end. When you open the door, the earth to light the main lamp is provided by the timer relay. The main lamp can also get an earth to light it from the manual rocker switch. The map reading lamp only can get its earth to light it from the manual rocker switch.
I suspect that the manual rocker switch when operated, does not light up either lamp at the moment.
With the battery disconnected, detach the lamp unit, and see if there is a Black lead lurking around behind it.

Cheers. There is a black lead behind the lamp unit, but it is earthed to the ceiling via a screw at one end, and the other end disappears into the electronics for the remote door lock thingy. Maybe the earth wire is missing?

Cheers. There is a black lead behind the lamp unit, but it is earthed to the ceiling via a screw at one end,

I cannot see why it is "earthed to the ceiling". My feeling is to undo the screw and attach it to the body of the lamp unit, mine is under one of the attachment screws which holds the unit up. Any chance of a pic of how it is at the moment, ie:- where the black lead is attached to
Just one thing to watch, if you are doing this work, even with the door closed & the light off, there is live12volt on the lamp holders and it is very easy for the black lead to accidently touch one and blow the fuse.........dont ask me how I know .....Disconnect the battery before moving the earth around but pic first if pos.

John

Cheers. Here's what it looks like. This is taken from sitting in the driver's seat looking up, erm, obviously. I also noticed while i was taking this that there's another bolt in the ceiling with no wire coming from it. Could be that that was once the earth?



Alex

[mettersl]

The wiring diagram shows two earth's- one to the ceiling (I guess the metal frame surround) and one via the loom-
In your situation I'd just connect the black wire to the right terminal- what's the worst that can happen- a blown fuse? But then again its different when its your own car.
Cheers
Lee

Cheers. Here's what it looks like. This is taken from sitting in the driver's seat looking up, erm, obviously. I also noticed while i was taking this that there's another bolt in the ceiling with no wire coming from it. Could be that that was once the earth?



Alex

Where is the pic

That's odd. I can see it on my screen. I uploaded it from photobucket!

try this:


Ta
Alex

.

Thats the problem Alex, take the earth from under the bolt, and put it under the screw holding the lamp unit up. Pass it through the unit, and put it between the screw head, and the earth tag of the lamp unit, refit it, reconnect the battery, and I think you will find it will work
This is what it should look like, note where the Black earth wire is connected.

Hope this helps.

John

Nope. Nothing. My gut feeling is that that earth is meant to be on that bolt and that it's something to do with the receiver for the remote central locking unit. There is a little cutaway indent next to the bolt hole in which the terminal sits perfectly so it doesn't get bent when the bolt is screwed in.

The other bolt has a similar dent, which would make me wonder if i'm missing an earth that goes from there to... the third spade terminal on the back of the light switch unit at the top of the picture here:



Anyone wanna crack their light open and see what it looks like behind there?

Alex. Can you post a pic of the lamp unit, with the same view as I took mine please.

Like this? Sorry for the low quality



Alex

Right Alex, you can do one of two things, apart from the extra spade connector in your fitting, it appears to have the same earth connection on the LHS under the attachment screw, as mine has, so I would detach the black earth wire from under the small bolt, which is not a regular earthpoint as it happens, and ,as I said before, attach it as per my pic. The light should work, if it does not, you have a switch prob in the light unit, ( I have had that one ), or you could try getting a piece if wire, putting a crimp eye on one end, and put it under the bolt where the black wire is anchored, and crimp a 3/16, or 1/4in female connector (whichever is the right size) on the other end, and connect it to the spare connector on your unit. My preference would be the simple first one.
I suspect that in the past someone has not reconnected the light correctly, after its removal for some reason
Let us know how you get on.

John

PS. If you connect up, and it still does not work, dis batt again, detach the unit from roof, let unit hang on wires, put a small nut and bolt through the black wire`s tag, and bolt it to the LH brass earth strap fixing hole in the unit.(see our pics). Reconnect battery, get in car, close door, wait for main lamp to go out, then try switch, if no light, clean contacts of the switch, you should be able to get to them through the hole in the back. If the switch has not been used for a long time, the switch contacts could be tarnished due to the brass being unplated. I have had this problem myself a while ago. If for some reason the light stops working when you open the door, check fuse, it is very easily blown, as most of the bare metal in the unit has 12volts on it all the time, even when the lights are out