Hello I will help you with your question,
Start at the brake light switch under the dash at the shaft of the brake pedal, pull the connector and use a paperclip to jump from the red to the green wire. See if the lights come on.
Does the third light work? If it does you do not have to go to the switch but there is a break at a splice.
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Ok, then start at the switch with the jumper and see if you have power at the paperclip while it is installed.
Here's a picture to help
Click here for picture
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Niether, you use a paperclip to connect them. The paperclip will have 12 volts on it so don't let it touch anything metal.
Tell me if there is 12 volts at the paperclip when you have it jumpered to the connector.
And please tell me if the brake lights are on with the paperclip installed
No you stick the two ends of the paperclip into the connector to connect the red wire which should have 12 volts to the green wire which runs back to your brake lights. Slide the paperclip into the connector to jumper the two wires together.
Let me know what happens and if you have 12 volts to the paperclip once you have it installed.
Let me know what you find
Replace the brake switch.
Make sure the lights are off with the pedal up but if you are the original owner and have less than 60,000 miles Hyundai will do this for free. The switch will have to come from Hyundai in any case.
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