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 and short in wire harness between HV ECU and battery ECU.
PREPARATION:

Disconnect the connector from the battery ECU and the HV ECU

CHECK:

Check that the communication bus line is not short or open.

Terminals for checking open and short:

Fig 1: Identifying HV ECU & Battery ECU Terminals Used For Checking For Open Or Shorts
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK:

No open or short.
1. NG: Repair or replace the wire harness.
2. OK: Go to next step.
Stop operation of all optional electric products for vehicle and check if same DTC is stored.
1. NO: Stop using product that causes noise.
2. YES: Go to next step.
Replace the HV ECU.