Hello, I trust this finds you all well. I have a 2008 Lexus GS350. wonderful car. However, last week I got a po715 code. The car drives fine, no vibrations, just wont shift upwards of 4 gear. When I clear the code it runs fine and shifts fine, even into 6th gear, and if I dont let off the gas, ie set cruise it will stay in 6th. But when I let off and accelerate it doesn't go above 4th gear again. I replaced the input shaft speed sensor, at the rear of the tranny, (rear wheel drive,) on the drivers side. It made no difference at all. At the sensor connection the wiring looks fine.
Can someone be so kind as to help lead me in the right direction? I would appreciate it.

Thank you!

Ted

 

I did some search and this video may help you. Video says the input sensor when malfunctions it receives signal from the output speed sensor.

This part is in 14:00 but the entire video shows you pin ohm levels. So you can grab a voltmeter and measure ohm in each pin in the harness to see which sensor is acting up. If you do find the levels not in spec, see what sensor it is unplug its plug and then test for to see if there any break in any of the wire to the sensor. Next test the sensor itself

https://at-manuals.com/manuals/a761e-a760e-f-h/