Map Light wiring and bulb questions

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1971 Mach 1 - "Day 2" restoration; 351C/FMX, trick flow heads, roller cam conversion, CAA AC kit, upgraded springs/shocks & close-ratio steering box
I recently scored a nice map light (Thank you 87Fox72Mach!). I understand that I'll need  to 'engineer' my own harness to power it, but first I am looking for the right bulb to use (or suitable replacement). What are folks on the forum using? I've searched at  least 17 pages of search results with no luck on this topic. 

I am also curious about how other have dealt with building their own wiring, or where they tapped  into an existing (non convenience group) harness - questions I have are:

- Where have other spliced into the old harness?

- Are there suitable unused plugs I can use where I'll only need to build an extension or pigtail type harness to power the light? 

- Where did the convenience harness plug into the dash wiring?

Thanks!

Jim

 
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Not for sure exactly where the convenience group plug will be behind the dash. If you go to the wiki pages and look at the last page for the 71 schematics you will see the interior lights wiring diagram.  If you cannot find the plug you will need to splice into the dome light circuit at the door switch.  Pay attention to how the wiring changes at the map light connection. This allows for the map light to come on when opening the doors or staying off and using the switch to turn it on.   I added mine a few years ago and was able to use a connector from part of a old harness I had.  

 
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The map light bulb, as shown in the shop manual, is a 212, so that LED should work. Mine didn't come with a map light, so I made my own.

You'll need to find two wires to operate your map light, one a key on run/accessory for the on side of the switch and the other from the dome light circuit so the map light comes on when a door is opened or the dome light is turned on. The dome light wire you need to look for is black with a light blue stripe. 

A good one for the key on run/accessory will be a white wire with purple stripe that powers the radio and a couple of other things, like backup light.

 
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Not to disagree with what Don said but if you have an original map light it needs to get wired into the door switch circuit for it to work right.  Easy place to tap in is behind the glove compart.  You will take the light green -yellow stripe wire from the map light and tie it in to the black - light blue stripe of the door switch wiring.  You will then take the black - light blue stripe from the map light and tie it in to the light green - yellow stripe of the door switch.  The black wire from the map light goes to ground.  I know this doesn't sound right but it is.  This allow the map light to come on when you open your doors or you can move the switch and it will only come on when you use the switch.  

Map light.png  

 
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I agree that's the way the original is wired, but that leaves the possibility that the map light can be left on after the engine is off and the car is exited. I wired mine so that the map light can only be turned on when the key is in run or accessory, as well as when the dome light is on when the doors are open, and recommended that.

 
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Just a follow-up to close the thread - I ordered a 3-wire connector from wiringprodcuts.com, and used that to make a simple harness that extended the wiring along the factory route to the door pillar wiring for the dome light. I grounded on the panel behind the kick panel. To maximize light output and keep current low, I used the LED I linked to above. Buttoned it up Saturday afternoon, and works great.

Map Light.JPG

 
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