HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for NICKEL METAL HYDRIDE BATTERY): HV Battery High-voltage Line Circuit; 2019 - 2020 MY Avalon HV [04/2018

Check the continuity in the high-voltage line from the HV battery to the inverter.

Check the connection condition and for an open circuit in the frame wire from the service plug grip, EV electric battery fuse and HV battery to the inverter and perform a function check of the system main relay.

Related Parts Check

SYSTEM DESCRIPTION

The HV battery high voltage is supplied to the inverter via the system main relay operation.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

This diagnostic procedure is referenced to in the diagnostic procedure of several DTCs.

If the result of this diagnostic procedure is normal, proceed as directed in the procedure for the DTC.

CAUTION:

Before the following operations are conducted, take precautions to prevent electric shock by turning the power switch off, wearing insulated gloves, and removing the service plug grip from HV battery.
- Inspecting the high-voltage system
- Disconnecting the low voltage connector of the inverter with converter assembly
- Disconnecting the low voltage connector of the HV battery
To prevent electric shock, make sure to remove the service plug grip to cut off the high voltage circuit before servicing the vehicle.
After removing the service plug grip from the HV battery, put it in your pocket to prevent other technicians from accidentally reconnecting it while you are working on the high-voltage system.

After removing the service plug grip, wait for at least 10 minutes before touching any of the high-voltage connectors or terminals. After waiting for 10 minutes, check the voltage at the terminals in the inspection point in the inverter with converter assembly. The voltage should be 0 V before beginning work.

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HINT:

Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

*a	Without waiting for 10 minutes

After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.

PROCEDURE

After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.

(d) Check for arc marks on the terminals for the HV floor under wire and inverter with converter assembly.

(a) Visually check the connection of the service plug grip to the HV battery. Remove the service plug grip and check for contamination.

Dirt or foreign matter has not entered the connectors, and there is no evidence of contamination.

After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.

(d) Disconnect the HV floor under wire connectors from the HV battery junction block assembly.

(e) Check for arc marks on the terminals of the HV floor under wire and the HV battery junction block assembly.

After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.

(f) Using a megohmmeter set to 500 V, measure the resistance according to the value(s) in the table below.

Be sure to set the megohmmeter to 500 V when performing this test. Using a setting higher than 500 V can result in damage to the component being inspected.

(g) Reconnect the HV floor under wire connector to the inverter with converter assembly.

(h) Reconnect the HV floor under wire connectors to the HV battery junction block assembly.

After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.