[eric06siennale]

I had this same issue come up on my 2006 with an installed used transmission from a more northern state (this will be important later). I had my transmission shop replace the "D" solenoid as I thought this was the issue.....turns out that didn't solve it. After some research on my part, and more diagnosis by the shop, it was found that there was a broken pin in the connector that exits the top of the transmission and connects to the TCM. Once the shop replaced the wiring harness and connector in the transmission, the problem was solved. I had found in forums that this issue was common in Tacoma's and Highlander's I believe. Some had even said that upon inspection, they didn't see any broken pins, but electrically, the connection was broken due to corrosion, hence my earlier comment as mine is a southern vehicle.