Inspection Procedure

WARNING: This page is about a different car, the 2002 Toyota Prius. However, it is still accessible from the selected car via links, so may be relevant.

Check for open, short and +B short in wire harness between HV ECU and accelerator pedal position sensor. . See HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION .
NOTE: The acceleration pedal position sensor circuit has +B short if the voltage at the HV ECU VPA1 or VPA2 terminal is more than 5V with the ignition ON.

Terminals for checking open and short:
1. NG: Repair or replace wire harness.
2. OK: Check and replace accelerator pedal position sensor. See PRIUS And REMOVAL & INSTALLATION (PRIUS) .
  
  Fig 1: Identifying Suggested Terminals For Probable Open Or Short Diagnosis
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