Interior lighting wiring help needed

[hembramacho]

Have wired an LED strip underneath the side step today, taking the feed from the switched earth for the sliding door switch, so that it comes on when the sliding door opens, and goes off when it closes.



This works fine.
However, I decided to wire in a switch so that it can be switched off when it's not needed to be on. The switch switches it off and on OK (plus it also switches off the internal light??) but I noticed that when the LED strip is on the voltmeter reads about 11.50v, which is about right, but when I switch it off and leave the door open the voltage drops straight away to about 10.50v and keeps dropping! When there's nothing actually on! It seems like there is a power surge or something?
Obviously i've done something wrong , so before I blow the Bongo up, if anyone has any ideas what the hell I've done, please share.

Cheers

Andrew

[missfixit70]

what voltmeter reading from where? How have you wired it?

[hembramacho]

what voltmeter reading from where? How have you wired it?

The voltmeter coming directly from the LB - one of DBO's gadgets!

Andrew

[missfixit70]

First thing I'd check is that the LB is charging or what has drained it down to 11.5v, that's a bit low. If you're sure it was ok before then i'd disconnect what you've done & see if it charges & holds a charge.

[hembramacho]

First thing I'd check is that the LB is charging or what has drained it down to 11.5v, that's a bit low. If you're sure it was ok before then i'd disconnect what you've done & see if it charges & holds a charge.

The LB definitely charges via the Willington, as it goes up to 14 something volts when running the engine. TBH I've always thought the LB runs down quicker than it should as it always seems to be on mid 11.50v or lower - I did take it back in the beginning but they said they checked it and it definatley held it's charge. Hmm......
Anyhow, with the lights, am now wondering if I connected the correct spades to the correct terminals on the switch. The 3 terminals have a +, A and an earth symbol.
I wired it up with the 12v + going to the +, the switched earth going to A, and a seperate wire earthed from the chassis going to the earth symbol. Is it worth swapping the earth/switched earth spades round to see what happens?

Cheers for the replys by the way.

Andrew

[missfixit70]

11.5 volts is not a fully charged LB by any means, should be above 12.5v especially if it's newish, you are being fed BS I suspect, I would disconnect, put it on an intelligent charger for a day or two until it is fully charged (if it will), see if it'll hold a charge, do a load test on it if it seems to be holding. only then can you even really think about faultfinding on any wiring, or values are meaningless IMO, you'l be Pi55ing into the wind.

[hembramacho]

11.5 volts is not a fully charged LB by any means, should be above 12.5v especially if it's newish, you are being fed BS I suspect, I would disconnect, put it on an intelligent charger for a day or two until it is fully charged (if it will), see if it'll hold a charge, do a load test on it if it seems to be holding. only then can you even really think about faultfinding on any wiring, or values are meaningless IMO, you'l be Pi55ing into the wind.

Thanks Kirsty. Having read through previous posts regarding what voltage number means what percentage of charge should be in the LB, I've always doubted the battery. Will test it properly, although I do suspect you're right on that one.

Cheers

Andrew

[bakey]

Still adding bits!

[daveblueozzie]

what voltmeter reading from where? How have you wired it?

The voltmeter coming directly from the LB - one of DBO's gadgets!

Andrew

the LED display (voltmeter gadget)is connected to the LB and gives a constant reading for the LB.
Like Kirsty says, you have deffo got a drain from somewhere,it should not drop that low,this happened to mine ,found out i had a duff battery but also the radio was draining the battery within a week.
As for the switch i have something similar, i just put the switch on the live wire from the light i fitted,(but only a two spade switch) simple on off, to break the circuit.

[g8dhe]

The switch switches it off and on OK (plus it also switches off the internal light??) but I noticed that when the LED strip is on the voltmeter reads about 11.50v, which is about right, but when I switch it off and leave the door open the voltage drops straight away to about 10.50v and keeps dropping!

It sounds like the extra switch you have added. It sounds like you connected one wire to the switched earth from the door switch, and the other one it sounds like from the fault condition you have wired to the +12v supply going to the LED strip - WRONG

What sort of switch have you added ? How many connections does it have ? Can you put a photo up of the connections ?
Next where are you getting the +12v supply from for the LED light ?
The extra switch should be between the switched door earth and the -ve of the LED light, the +ve of the LED light should go to the +12v supply directly.

I'm guessing a bit on some of the connections you might have made, but if you can supply the above details it will help to locate the problem !

[hembramacho]

Hi Geoff.
My switch has a +, A and earth symbol terminal. I've wired the 12v live to the +, the switched earth to the A and an extra chassided(!) earth to the earth symbol terminal.
Does that make sense?

Andrew

[hembramacho]

Still adding bits!

Always! - how's yours doin'

Andrew

[g8dhe]

My switch has a +, A and earth symbol terminal. I've wired the 12v live to the +, the switched earth to the A and an extra chassided(!) earth to the earth symbol terminal.

Ah yes it does explain the fault! Disconnect the +12v from your switch, as your shorting out the supply - which is why the battery is draining rapidly - I'm suprised the fuse hasn't blown - you might find that the existing switch could do with a clean as its obviously not putting out a very good earth!

Where is the LED light connected to the switch however ? The best way to connect is;
+12 volt supply to the +ve of the LED light
-ve of LED light to one side of the switch and the other side of the switch to the switched earth from the door switch.
Its not totally clear from the markings which connection is which but you only want TWO connections in use on the switch, and don't bring the +12 volts any where near the switch at all.

[madmile]

Hi Geoff.
My switch has a +, A and earth symbol terminal. I've wired the 12v live to the +, the switched earth to the A and an extra chassided(!) earth to the earth symbol terminal.
Does that make sense?

Andrew

On these switches, + is the live feed, obviously earth is earth, and 'A' is the live switched feed to the application - ie the light.
Always difficult without actually seeing it, but you could take the + feed into the switch, and then onto the light from'A'.
This would switch the light on assuming it had a continuous earth.

You could use the switch without the earth (this is usually there for the benefit of an LED on the switch to show its on).

If however you are trying to use the light as a courtesy light that comes on with the door open, then you could take a + feed from the original light wiring (or any other suitably fused wire) and take it to the + on the switch. Then take the 'A' on the switch to the + on the light. Take the - on the light to the contact button on the side door. The lights will come on when the door is open, but can now be manually switched off for times during the day when you may well want to leave the door open but dont want lights on for hours on end. This is how I would wire a courtesy light, but someone else may do it differently.

Edit - just seen Geoff's new post, and that was going to be my other suggestion. You are just then using the switch as a make / break in the circuit, but now on the earth side. The only odd thing about doing it this way is that you are now connecting one part of the earth to the + on the switch and the other part to the A+. This just looks confusing if you look at the switch, but should work perfectly well. Just may confuse someone later on who works on the vehicle. You can just buy the same switch with only 2 connections which would make things clearer as you just put it in the wire that you want to switch.
Hope this isnt too confusing, but its late and Ive had a long day .

[hembramacho]

Cheers for that guys - will have another fiddle when I get a chance.

Thanks again

Andrew