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Electrical Map Light / Snake Light

  • Thread starter Thread starter whitefoxgt
  • Start date Start date Jan 6, 2022
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whitefoxgt

Member
Feb 18, 2004
12
2
13
Jan 6, 2022
#1
  • Jan 6, 2022
  • #1
1990 GT Hatchback. Snake light only works when doors are open or I turn the dimmer switch on all the way which brings on all the interior lights. All the wires look stock and haven’t been touched. Any ideas?

Thank you,
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
27,866
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polk county florida
Jan 6, 2022
#2
  • Jan 6, 2022
  • #2
What snake light?
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,215
17,898
224
Massachusetts
Jan 6, 2022
#3
  • Jan 6, 2022
  • #3
Is your glove box light functional and does it have all the wires? There should be two Light Green/Yellow wires into the glove box light. One is the feed from fuse #8, and the other goes up to the map and vanity lights to feed them.

Tapped into this wire is the right courtesy light switch, which feeds the left switch and then to the dimmer.

My guess is you lost power from/to the glovebox light somehow and you are not feeding the map light normally and only when the dimmer switch is activated. I would test for power at the glovebox light and then from the LG/Y wire on the glovebox light up to the map light to see if you have continuty and constant power there.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,215
17,898
224
Massachusetts
Jan 7, 2022
#4
  • Jan 7, 2022
  • #4
Here are the diagrams. The confusing part is they show the convertible, sunroof and “no sunroof” cars on the same page. The middle pair of wires apply to cars with the map light.



 
Last edited: Jan 7, 2022
Reactions: whitefoxgt
W

whitefoxgt

Member
Feb 18, 2004
12
2
13
Jan 7, 2022
#5
  • Jan 7, 2022
  • #5
Mustang5L5 said:
Is your glove box light functional and does it have all the wires? There should be two Light Green/Yellow wires into the glove box light. One is the feed from fuse #8, and the other goes up to the map and vanity lights to feed them.

Tapped into this wire is the right courtesy light switch, which feeds the left switch and then to the dimmer.

My guess is you lost power from/to the glovebox light somehow and you are not feeding the map light normally and only when the dimmer switch is activated. I would test for power at the glovebox light and then from the LG/Y wire on the glovebox light up to the map light to see if you have continuty and constant power there.
Click to expand...
This makes a lot of sense. I know that the door jamb switch on the passenger side has failed. When the Passenger door is open none of the courtesy lights come on. Only when the drivers door is open will the lights come on. I will start in the glove box and work my way around. Thank you for the info, this was very helpful.
 
W

whitefoxgt

Member
Feb 18, 2004
12
2
13
Jan 7, 2022
#6
  • Jan 7, 2022
  • #6
General karthief said:
What snake light?
Click to expand...
 
Reactions: General karthief

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
27,866
10,539
203
polk county florida
Jan 7, 2022
#7
  • Jan 7, 2022
  • #7
Try spraying the switch on the door jam with wd40 and pushing, I believe it's just a grounding switch and the spring gets gunked up and sticks, they rarely fail.
 
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