WARNING: This page is about a different car, the 2003 Toyota Prius, 2002 Toyota Prius, and 2001 Toyota Prius. However, it is still accessible from the selected car via links, so may be relevant.
ABS circuits and wiring harness can be tested by backprobing ABS ECU connectors and comparing measured voltages with ABS ECU standard values chart. See Fig 1-Fig 3
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