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> Interior light, My next electrical gremlin
tomh
post Sep 3 2017, 11:54 AM
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So now my next electrical problem is my interior light on the back pad between the seats. The light and fixture are brand new and the wires seem to be fine.I tested the light out side of the car and it does work.I grounded it with a pig tail and it still wouldn't light so I checked it with a meter and it doesn't seem to have much power if any it think I got a reading of a couple of volts but still not sure about that. It will not light on any of the switch positions. Could it be the door switches? What other electrical items are on that circuit. Which fuse in the stock fuse block is it?
Thanks all!
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rgalla9146
post Sep 3 2017, 12:59 PM
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QUOTE(tomh @ Sep 3 2017, 01:54 PM) *

So now my next electrical problem is my interior light on the back pad between the seats. The light and fixture are brand new and the wires seem to be fine.I tested the light out side of the car and it does work.I grounded it with a pig tail and it still wouldn't light so I checked it with a meter and it doesn't seem to have much power if any it think I got a reading of a couple of volts but still not sure about that. It will not light on any of the switch positions. Could it be the door switches? What other electrical items are on that circuit. Which fuse in the stock fuse block is it?
Thanks all!


Remove each door switch and clean the pointed connection and the 'v' shape receiver with an Xacto knife or a razor blade.
Slide the push-on connectors on and off their blades repeatedly to improve connection.
As I recall the switches are all on the ground side of the lamp.
The power wire is less than 12v ? .... (the green wire) check that at the fuse box connection.
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ConeDodger
post Sep 3 2017, 02:58 PM
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One of the first things any 914 owner should do when they get their car is chase down and clean the dozen or so grounds. Makes a bunch of gremlins go away! (IMG:style_emoticons/default/evilgrin.gif)
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914_teener
post Sep 3 2017, 03:34 PM
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The door switches ground tje light.

Mine were just worn out.
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Matty900
post Sep 3 2017, 03:53 PM
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QUOTE(ConeDodger @ Sep 3 2017, 01:58 PM) *

One of the first things any 914 owner should do when they get their car is chase down and clean the dozen or so grounds. Makes a bunch of gremlins go away! (IMG:style_emoticons/default/evilgrin.gif)

(IMG:style_emoticons/default/agree.gif)
I use a dremel tool with a wire wheel brush on a flexible wand attachment to get off all the corrosion & or paint


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Dave_Darling
post Sep 3 2017, 03:58 PM
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The power wire should have constant 12V. Check from it to a good ground, like the battery (-) terminal. If it's less than 12V, check the (+) side of the circuit for dirty or bad connections.

The ground side of the circuit is generally more likely to give trouble, so that should definitely be checked as well.

--DD
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ConeDodger
post Sep 3 2017, 04:01 PM
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QUOTE(Matty900 @ Sep 3 2017, 06:53 PM) *

QUOTE(ConeDodger @ Sep 3 2017, 01:58 PM) *

One of the first things any 914 owner should do when they get their car is chase down and clean the dozen or so grounds. Makes a bunch of gremlins go away! (IMG:style_emoticons/default/evilgrin.gif)

(IMG:style_emoticons/default/agree.gif)
I use a dremel tool with a wire wheel brush on a flexible wand attachment to get off all the corrosion & or paint


I believe Bowlsby has a map of 914 ground locations on his site...
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tomh
post Sep 3 2017, 05:39 PM
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Both of the wires going to the fixture is black with stripes. One of the wires has a larger female connector and one is smaller. I'm assuming the smaller is the ground.
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Dave_Darling
post Sep 3 2017, 07:33 PM
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There should be three wires. One black, one brown, one brown with a white stripe.

Sounds like someone has monkeyed with your wiring. You may want to pull the back pad out and see what has been done.

--DD
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rgalla9146
post Sep 3 2017, 08:44 PM
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QUOTE(Dave_Darling @ Sep 3 2017, 09:33 PM) *

There should be three wires. One black, one brown, one brown with a white stripe.

Sounds like someone has monkeyed with your wiring. You may want to pull the back pad out and see what has been done.

--DD


Right again Dave.
When I said 'green wire' I was confused with the wires for the rear defog.
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raynekat
post Sep 3 2017, 08:45 PM
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Often times the door contact switches will be bad.
Especially the early ones that have 4 terminals.
Both were bad on my 71 and I went through about a half a dozen of supposed good switches before I found a set that work.

If the door switch is bad, there is no way that interior light is going to work correctly.
And it's true; you need a full 12V+ for that light to light up.
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whitetwinturbo
post Sep 4 2017, 01:33 PM
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What is link to all the "ground" locations (IMG:style_emoticons/default/beer.gif) ?
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tomh
post Sep 4 2017, 06:45 PM
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So I removed the back pad and the only wires long enough to reach the light are all brown with white stripes. There is a connector with 3 wires attached and a connector with 1 wire then there is one with a smaller connector. All the other wires down there are the seat and seat belt stuff. I tried both of the connectors and still no power to the light. Both of the door switches seem ok with good connections and a strong spring also I did clean the "v" contact as best I could.
Am I missing something here?
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raynekat
post Sep 4 2017, 09:53 PM
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When you say the switch has good connections, what do you mean?
With the button or spring out, dId you check each pair of pins for continuity with a multimeter?
That is the only way to really know.
With the button in or spring compressed, the multimeter should show lack of continuity across each pair of pins.
These switches really do fail after a number of years and bazillions of times opening and closing the doors.
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dangrouche
post Sep 4 2017, 10:10 PM
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QUOTE(whitetwinturbo @ Sep 4 2017, 12:33 PM) *

What is link to all the "ground" locations (IMG:style_emoticons/default/beer.gif) ?

here's Bowlsby's diagram


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tomh
post Sep 4 2017, 10:37 PM
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I'll test the switches and see what I come up with.
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carcus
post Sep 4 2017, 10:55 PM
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I have the same problem as well. But I have plenty of time to fix it. Most of my OEM wiring was dry rotted. Mine seems to be the door switch. The middle setting will keep the light on but will not go on with the door open.
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tomh
post Sep 5 2017, 08:12 AM
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My problem is power to the light, weather the switch is good or not I still should have 12 volts to one of the wires,all the switches do is ground it to make it light up that's why my switches probably are not my problem.
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914_teener
post Sep 5 2017, 09:53 AM
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So how did you test it then? That would be helpful to know.

You should have 12V at the black red striped wire. Assuming the car is a 73. The power comes off the fused side of fuse 11. Test the wire at the end for 12v against a known good ground.

If you find 12v there then the power feed is good. If not then the wire is suspect if the fuse terminal checks at 12V.

Make sure the connections are clean.

Hope this helps.
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Dave_Darling
post Sep 5 2017, 09:57 AM
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Find the solid brown wire, and find the black (or black/red) wire. The latter has a constant +12V and is how the light gets powered.

--DD
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