None -------Starting in 1999 the internal mode switch was added to the 4T65E transmission. This switch serves the same purpose as the typical external neutral safety switch. The Internal mode switch is inside the transmission. You can verify that you have the internal mode switch if you have 19 wires going into the transmission case connector. ( large round connector on top driverside of transmission) This part is not usually replaced during a rebuild, unless there were prior diagnostic codes for a malfunctioning switch. Most shops will reuse the original switch. The switch can be improperly assembled, which can cause drivability issues. Unfortunately, due to the limited access the transmission often must be removed to be able to remove the side pan to get into the transmission to replace the switch.
Answers & Comments
None -------Starting in 1999 the internal mode switch was added to the 4T65E transmission. This switch serves the same purpose as the typical external neutral safety switch. The Internal mode switch is inside the transmission. You can verify that you have the internal mode switch if you have 19 wires going into the transmission case connector. ( large round connector on top driverside of transmission)
This part is not usually replaced during a rebuild, unless there were prior diagnostic codes for a malfunctioning switch. Most shops will reuse the original switch. The switch can be improperly assembled, which can cause drivability issues. Unfortunately, due to the limited access the transmission often must be removed to be able to remove the side pan to get into the transmission to replace the switch.