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Discussion Starter #1
Guys I'm completely lost...My car has all new wiring harness all new courtesy lights and switches and bulbs... Including all new dash switches. I have wired multiple cars and I have never had this much problem. I've installed a new factory wiring harness...What has me stumped is I can run a jumper from the red and black wire on the headlight switch to the blue and black courtesy light wires and everything will come on and work as it should, but if I turn the switch to turn the courtesy lights on, nothing happens. I can open the doors and nothing happens. I know the grounds are working because the lights wouldn't come on with a jumper wire if they wasn't grounded. Even the glove box switch and GT Door courtesy lights are new and it will not work. I've put three new headlight switches which all work as they should just not the courtesy lights...I've also put in two sets of new door switches still nothing. Why would they work with a jumper switch but not any other way.....Ive cleaned all the connections on the harness and made sure they connected to the headlight switch ...I've put the jumper on the tops of the wires where they go through the top of the pigtail and I've run them into the connectors on the bottom of the pigtail and all lights come on.....Just stumped...
 

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Have you used a test probe to see if the feed has power?

 

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Discussion Starter #5
They do not have power with the doors open or lights switch turned to courtesy...but once again I know there is isn't a short since they all work when jumped off the headlight switch pigtail
 

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The BLU/BLK wires are the "load" side of the circuit and are connected directly to the bulbs. A jumper to a 12V source to the BLU/BLK will cause them to light, if each bulb is properly grounded. The BLU/BLK wire will get power when the door switches close or when the headlamp switch is rotated to close the courtesy lamp "override" function. The courtesy lamp circuit gets its power on the GRN/YEL wires, which go to each door switch and the glove box lamp and is hot all the time. I'd check the 7-1/2 amp fuse in the fuse panel for power on both sides....
 

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I agree with woodchuck. Be sure to check that you have power at the hot prongs on the fuse block, at the hot end of the fuse, at the cold end of the fuse and at the cold prongs of the fuse block. If the prongs that hold the fuse are dirty/corroded, they won't make contact with the caps on the fuse.
 

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Discussion Starter #8
Perfect thanks guys let me give this a try I thought the biue and black wire was the hot....I'll be back with you asap
 
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