High Voltage Safety; High Voltage Safety System - Toyota AVALON Hybrid Dismantling Manual

High Voltage Safety

The HV battery pack powers the high voltage electrical system with DC electricity. Positive
and negative orange colored high voltage power cables are routed from the battery pack,
under the vehicle floor pan, to the inverter/converter. The inverter/converter contains a
circuit that boosts the HV battery voltage from 244.8 to 650 Volts DC. The
inverter/converter creates 3-phase AC to power the motor. Power cables are routed from the
inverter/converter to each high voltage motor (electric motor, electric generator, and A/C
compressor). The following systems are intended to help keep occupants in the vehicle and
emergency responders safe from high voltage electricity:

High Voltage Safety System


A high voltage fuse * provides short circuit protection in the HV battery pack.

Positive and negative high voltage power cables * connected to the HV battery pack are
controlled by 12 Volt normally open relays *. When the vehicle is shut off, the relays stop
electrical flow from leaving the HV battery pack.
WARNING:
・ The high voltage system may remain powered for up to 10
minutes after the vehicle is shut off or disabled. To prevent
serious injury or death from severe burns or electric shock,
avoid touching, cutting, or opening any orange high voltage
power cable or high voltage component.

Both positive and negative power cables * are insulated from the metal body. High voltage
electricity flows through these cables and not through the metal vehicle body. The metal vehicle
body is safe to touch because it is insulated from the high voltage components.

A ground fault monitor in the hybrid vehicle computer * continuously monitors for high voltage
leakage to the metal chassis while the vehicle is running. If a malfunction is detected, the hybrid
vehicle computer * will illuminate the master warning light
indicate "Check Hybrid System" on the multi-information display.

The HV battery pack relays will automatically open to stop electricity flow in a collision sufficient
to activate the SRS.
*Numbers apply to the illustration on the following page.
in the instrument cluster and
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