So my third brake light works but not my other brake lights I replaced the bulbs an fuses anyone have an idea?

The third brake light and the regular brake light are supposed to be electrically tied together. The voltage is getting to the third brake light so follow the wires to the regular brake lights. Something is disconnected.

1. I would first check all the bulbs. Then TSB #03-08-42-007A - (Jan 9, 2004) Tail Lamp/Brake Lamp Bulb Inoperative (Replace Bulb and/or Circuit Board) 2000-2004 Chevrolet Venture 2000-2004 Oldsmobile Silhouette 2000-2004 Pontiac Montana Revised to add model years (from 03-08-42-007). Condition Some customers may comment that the upper left hand or right hand tail lamp/brake lamp bulb is inoperative. Cause This condition may be the result of moisture entering the lamp housing and changing the bulbs resistance, causing the bulb to burn out and or melting the circuit board. Correction Replace the burned out bulb and the circuit board if needed. Apply dielectric lubricant or dielectric grease to the left hand and right hand tail lamp bulb terminals. Parts Info Part # Description 12377900 (10953529 in Canada) Dielectric Lubricant 12345579 Dielectric Silicone Grease 12533713 Circuit Board-Left 12533714 Circuit Board-Right 9441839 Bulb

He says he replaced all the bulbs and fuses.

Well than as it says further in the TSB the circuit boards should be replaced.

Just find yourself some used taillights. I had the same issue with my 2001 - the contacts where the taillight bulb touches the metal contact plate has corroded - and it's more hassle than its worth (unless you're mechanically inclined) to replace them. I was able to get away with putting LED brake light bulbs on it, that require less power - and that seemed to fix the problem if buying new circuit boards/used taillights is not an option for you.