Diagnostic Aids
WARNING: This page is about a different car, the 2002 Toyota Sequoia. However, it is still accessible from the selected car via links, so may be relevant.
After confirming DTC P1120, use Toyota hand-held tester or scan tool to confirm throttle valve opening by reading ACCEL POS #1 and ACCEL POS #2 voltages with accelerator pedal released and depressed to determine probable cause for accelerator pedal position sensor. See THROTTLE VALVE OPENING VOLTAGE SPECIFICATIONS table. Using hand-held tester or scan tool, read FREEZE FRAME data. Freeze frame data records engine conditions when malfunction is detected.
THROTTLE VALVE OPENING VOLTAGE SPECIFICATIONS
| Accelerator Pedal Position & Accelerator Pedal Position Sensor Voltage Reading | Probable Cause | |
|---|---|---|
| Accelerator Pedal Released | ||
| ACCEL POS #1 (0 Volts) & ACCEL POS #2 (0 Volts) | Open In VC Circuit | |
| ACCEL POS #1 (0 Volts) & ACCEL POS #2 (1.8-2.7 Volts) | Open Or Short To Ground In VPA Circuit | |
| ACCEL POS #1 (.3-.9 Volt) & ACCEL POS #2 (0 Volts) | Open Or Short To Ground In VPA2 Circuit | |
| ACCEL POS #1 (5 Volts) & ACCEL POS #2 (5 Volts) | Open In E2 Circuit | |
| Accelerator Pedal Depressed | ||
| ACCEL POS #1 (0 Volts) & ACCEL POS #2 (0 Volts) | Open In VC Circuit | |
| ACCEL POS #1 (0 Volts) & ACCEL POS #2 (4.7-5.1 Volts) | Open Or Short To Ground In VPA Circuit | |
| ACCEL POS #1 (3.2-4.8 Volts) & ACCEL POS #2 (0 Volts) | Open Or Short To Ground In VPA2 Circuit | |
| ACCEL POS #1 (5 Volts) & ACCEL POS #2 (5 Volts) | Open In E2 Circuit | |