Toyota Avalon (XX50) 2019-2022 Service & Repair Manual: HV Battery High-voltage Line Circuit

DESCRIPTION

The cause of the malfunction may be the HV battery high-voltage line circuit.

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.

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.

  Click here

  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

NOTICE:

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.

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PROCEDURE

CAUTION:

Be sure to wear insulated gloves.

(a) Check that the service plug grip is not installed.

NOTICE:

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.

(b) Check that the bolts for the HV floor under wire is tightened to the specified torque, the HV floor under wire is connected securely, and there are no contact problems. Specified Condition: T = 8.0 N*m (82 kgf*cm, 71 in.*lbf)

(c) Disconnect the HV floor under wire from the inverter with converter assembly.

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

(e) Reconnect the HV floor under wire.

B

REPLACE MALFUNCTIONING PARTS

C

CONNECT SECURELY

A

CAUTION:

Be sure to wear insulated gloves.

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

OK:

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

(b) Install the service plug grip.

NG

REPLACE SERVICE PLUG GRIP

OK

CAUTION:

Be sure to wear insulated gloves.

(a) Remove the service plug grip.

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(b) Measure the resistance according to the value(s) in the table below. Standard Resistance: Tester Connection Condition Specified Condition Service plug grip terminals Always Below 1 Ω

*1 Service Plug Grip

(c) Install the service plug grip.

NG

REPLACE SERVICE PLUG GRIP

OK

CAUTION:

Be sure to wear insulated gloves and protective goggles.

(a) Remove the Hybrid battery terminal block.

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(b) Measure the resistance according to the value(s) in the table below. Standard Resistance: Tester Connection Condition Specified Condition Hybrid battery terminal block Always Below 1 Ω

*1 Hybrid Battery Terminal Block

(c) Install the Hybrid battery terminal block.

NG

REPLACE HYBRID BATTERY TERMINAL BLOCK

OK

CAUTION:

Be sure to wear insulated gloves.

(a) Check that the service plug grip is not installed.

NOTICE:

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.

(b) Remove the No. 1 HV battery cover panel RH.

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(c) Check that the HV floor under wire is connected securely, and there are no contact problems.

(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 wire and the HV battery junction block assembly.

(f) Reconnect the HV floor under wire.

(g) Install the No. 1 HV battery cover panel RH.

B

REPLACE MALFUNCTIONING PARTS

C

CONNECT SECURELY

A

CAUTION:

Be sure to wear insulated gloves.

(a) Check that the service plug grip is not installed.

NOTICE:

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.

(b) Remove the No. 1 HV battery cover panel RH.

Click here

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

(d) Disconnect the HV floor under wire connector from the inverter with converter assembly.

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

Standard Resistance:

NOTICE:

Be sure not to damage or deform the terminal being inspected.

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

NOTICE:

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.

Standard Resistance:

(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.

(i) Install the No. 1 HV battery cover panel RH.

NG

REPLACE HV FLOOR UNDER WIRE

OK

CAUTION:

Be sure to wear insulated gloves.

(a) Check that the service plug grip is not installed.

NOTICE:

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.

(b) Remove the HV battery junction block assembly.

Click here

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

Standard Resistance:

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

Standard Resistance:

(e) Install the HV battery junction block assembly.

NG

REPLACE HV BATTERY JUNCTION BLOCK ASSEMBLY

OK

CAUTION:

Be sure to wear insulated gloves.

(a) Check that the service plug grip is not installed.

NOTICE:

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.

(b) Remove the HV battery junction block assembly.

Click here

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

Standard Resistance:

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

Standard Resistance:

(e) Install the HV battery junction block assembly.

OK

HV BATTERY HIGH-VOLTAGE LINE CIRCUIT NORMAL (PERFORM NEXT STEP FOR REFERENCED DTC)

NG

REPLACE HV BATTERY JUNCTION BLOCK ASSEMBLY