Hello everyone,
I have a 2010 Lexus IS F (5.0 V8) and I’ve been struggling with a strange power window electrical issue for years.

Symptoms:
• Power windows sometimes have power 24/7, even when the car is OFF and locked.
• When the issue happens:
• All windows work from their own door switches
• Master switch on the driver door only controls the driver window
• Other windows do NOT respond from the master switch
• Driver window loses auto up/down (manual only).
• The illumination of the master switch buttons is OFF most of the time.
• When I press a window button, the light turns ON briefly.
• After releasing it, the light pulses/blinks for a few seconds, then turns OFF again.
• Passenger window switch illumination works normally, but control from the master switch is lost.

What I tried:
Replaced the master window switch (no change).
Battery replacements (multiple times).
Manual window initialization procedure found on YouTube.
Important details:
• The issue is intermittent.
• It sometimes temporarily fixes itself after reset or manipulation.

 

Do you have access to Techstream or GTS+ for diagnostics? The best way to test this is using the active test mode in Techstream or GTS+. It sounds like an intermittently bad connection in the wiring harness to me.