When I purchased my 04 SR5, I knew the actuator to engage Lo was not working. Like others I have read about, mine was just stuck from lack of use. After getting mine freed up, I Fabricated a trouble shooting tool that provides quick access to motor terminals and status of the 6 internal limit switches via a spare 12 wire plug from a donor vehicle. It uses a 9 volt battery and 6 LED’s to give an open or closed indication of the switches. I will attempt to upload a photo of the device.
Trent
Trent