I have two noise-related problems with my '99 Lexus rx300.
I had a similar annoying noise with the root cause being found in the air-mix servo. This servo motor box is one of three I believe and is located on the passenger side of the climate control system and accessed by removing the glove compartment (4 screws) and the panel down just above the floor. The servo in question is located behind a couple of heater tubes and you need a stubby phillips screwdriver to remove it. Disconnect the wiring plug. The servo has a damper actuator on one side. Hold with the actuator down and pry open the case. Don't fret if the snaps break because the unit is held together with screws anyway. Clean the contacts inside the box and re-lube the gears and contact plate with silicone grease. Reassemble and reinstall (kind of a pain). Works fine now in my auto (all is quiet again!) and saves hundreds of bucks vs. a visit to Lexus service. Shield the servo from heater tube heat with some aluminum reflective duct sealing tape. I think the heat breaks the lube down and caused the servo voltage to become errant, causing the servo to "hunt" and generate annoying noise. Good Luck.
Jun 13, 2009 |
1999 Lexus RX 300