P2128 Throttle/Pedal position sensor Problem. Jump to Latest Follow. Changed Pedal Position Sensor..Cleared the code..Drove around for about 20 miles..CEL Came right back on..Also this code also turns on my AT Light and puts my transmission in safe Mode..The sensor is submerged in hydraulic fluid continuously which causes case problems. Many times hydraulic flow is restricted or O ring sealing has initiated the problem. In any event, this is a complicated process better left to a transmission specialist.
The throttle position sensor (TPS) on your 1998-2002 1.8L equipped Toyota Corolla can be easily tested with just a multimeter. Not only is this test fast and easy but it's also a very accurate test and will let you know if the TPS is bad (or not).