Inspection Procedure

CAUTION:

Turn the ignition switch off before inspecting the high-voltage system. Before inspecting the high-voltage system, take safety precautions to prevent electrical shocks, such as wearing insulated gloves and removing the service plug grip. After removing the service plug grip, put it in your pocket to prevent other technicians from reconnecting it while you are working on the high-voltage system.
After disconnecting the service plug grip, wait for at least 5 minutes before touching any of the high-voltage connectors or terminals.

HINT:

At least 5 minutes is required to discharge the high-voltage capacitor inside the w/ converter inverter assembly.
In case of reproducing the problem, turning the ignition switch on and off repeatedly makes it easier to reproduce the problem. Do not repeat the operations of putting the vehicle into the READY-on state and turning the ignition switch off as these will activate a system main relay overheat protection.

CHECK HARNESS AND CONNECTOR (HV CONTROL ECU - MG ECU)

CAUTION: Be sure to wear insulated gloves.

Turn the ignition switch off and remove the service plug grip. (See HYBRID CONTROL SYSTEM )
Disconnect the H34 connector from the HV control ECU.
NOTE: Do not put the vehicle into the READY-on state with the service plug grip removed as this may cause a malfunction.
Remove the inverter cover. (See INVERTER WITH CONVERTER )
NOTE:
- Wrap the interlock round terminal for the inverter cover with vinyl tape to prevent it from shorting to ground.
- Be sure to prevent water in the reservoir tank from entering the inverter.
- Removing the inverter cover causes the MG ECU board to be exposed. Therefore, temporarily install the inverter cover for each area to be inspected.
Disconnect the I21 connector from the MG ECU.

Measure the resistance according to the value(s) in the table below.

Standard Resistance

TESTER CONNECTION AND SPECIFIED CONDITION

Tester Connection	Specified Condition
HSDN (H34-21) or HSDN (I21-26) - Body ground	10 kΩ or higher

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

Fig 1: Disconnecting H34 Connector From HV Control ECU

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: Go to next step

CHECK W/ CONVERTER INVERTER ASSEMBLY

CAUTION: Be sure to wear insulated gloves.

Measure the resistance according to the value(s) in the table below.

Standard Resistance

TESTER CONNECTION AND SPECIFIED CONDITION

Tester Connection	Specified Condition
HSDN (I21-26) - Body ground	2.65 to 3.55 kΩ

NG: REPLACE W/ CONVERTER INVERTER ASSEMBLY

Fig 2: Disconnecting I21 Connector From MG ECU

OK: REPLACE HYBRID VEHICLE CONTROL ECU