DTC P0A08-264: DC / DC Converter Status Circuit: Procedure

1. Connect the Techstream to the DLC3.
2. Turn the power switch on (IG).
3. Enter the following menus: Powertrain / EV / Trouble Codes.
4. Check if DTCs related to the EV control system are output.

   Result

   Result	Proceed to
   Only P0A08-264 is output, or DTCs other than the ones in the table below are also output.	A
   Any of the following DTCs including pending DTCs are also output.	B

   DTC No.	Relevant Diagnosis
   P0A78-121	Drive Motor "A" Inverter Performance
   P0A93-346	Inverter Cooling System Performance
   P0A94-127, 547, 548, 549	Inverter Performance
   P0AA6-526, 613	EV Battery Voltage System Isolation Fault
   P0ADB-227	EV Battery No. 1 Positive Contactor Control Circuit Low
   P0ADF-229	EV Battery Negative Contactor Control Circuit Low
   P0AE6-225	EV Battery Precharge Contactor Control Circuit Low
   P0C73-776	Motor Electronics Coolant Pump "A" Control Performance
   P3004-131, 803	High Voltage Power Resource
   P314A-828	Inverter Coolant Pump Speed Signal

5. Turn the power switch off.

B → See step   32 

A: Go to next step 

1. Remove the IGCT NO. 2 fuse from the No. 2 motor compartment relay block.
2. Measure the resistance according to the value(s) in the table below.
   Fig 1: Identifying IGCT No. 2 Fuse On No. 2 Motor Compartment Relay Block

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Resistance

   Tester Connection	Switch Condition	Specified Condition
   IGCT NO. 2 fuse terminals	Always	Below 1 Ω

   TEXT IN ILLUSTRATION
   
   

   *1	No. 2 Motor Compartment Relay Block
   *2	IGCT NO. 2 Fuse

3. Install the IGCT NO. 2 fuse.

NG → See step   23 

OK: Go to next step 

1. Remove the DCDC-S fuse from the No. 1 motor compartment relay block.
   Fig 2: Identifying DCDC-S Fuse On No. 1 Motor Compartment Relay Block

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Switch Condition	Specified Condition
   DCDC-S fuse terminals	Always	Below 1 Ω

   TEXT IN ILLUSTRATION
   
   

   *1	No. 1 Motor Compartment Relay Block
   *2	DCDC-S Fuse

3. Install the DCDC-S fuse.

NG → See step   25 

OK: Go to next step 

1. Remove the IGCT fuse from the No. 1 motor compartment relay block.
   Fig 3: Identifying IGCT Fuse On No. 1 Motor Compartment Relay Block

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Switch Condition	Specified Condition
   IGCT fuse terminals	Always	Below 1 Ω

   TEXT IN ILLUSTRATION
   
   

   *1	No. 1 Motor Compartment Relay Block
   *2	IGCT Fuse

3. Install the IGCT fuse.

NG → See step   27 

OK: Go to next step 

1. Disconnect the cable from the positive (+) auxiliary battery terminal.
   Fig 4: Measuring Resistance Of Auxiliary Battery Positive (+) Terminal

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Switch Condition	Specified Condition
   B1-1 - Auxiliary battery positive (+) terminal	Always	Below 1 Ω

3. Connect the cable to the positive (+) auxiliary battery terminal.

NG → REPLACE FUSIBLE LINK BLOCK ASSEMBLY (DC/DC) 

OK: Go to next step 

1. Check the connector connections and contact pressure of the relevant terminals for the power management control ECU connectors.
   Fig 5: Identifying Power Management Control ECU Connectors

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   OK

   The connectors are connected securely and there are no contact pressure problems.

NG → CONNECT SECURELY 

OK: Go to next step 

1. Check that the service plug grip is not installed.
   NOTE:

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

   NOTE:

   Before disconnecting the connector, confirm that it is properly connected by checking that the locking claws are engaged and that the connector does not pull out.

   Fig 6: Identifying Inverter With Converter Assembly Connector Lever

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Check the connection of the low voltage connector of the inverter with converter assembly.

   OK

   The connector is connected securely and there are no contact problems.

   HINT: 

   When connecting the connector, insert it with the locking lever in the raised position. Rotate the lever downward and make sure that the connector is pulled into its socket. When the locking lever is in its fully closed position, a click will be heard as its locking claws engage. After the click is heard, pull up on the connector to confirm that it is properly connected.

NG → CONNECT SECURELY 

OK: Go to next step 

1. Check that the service plug grip is not installed.
   NOTE:

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

2. Remove the upper inverter cover sub-assembly from the inverter with converter assembly.
   Fig 7: Identifying Upper Inverter Cover Sub-Assembly Bolts

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Using a megohmmeter set to 500 V, measure the insulation resistance according to the value(s) in the table below.
   Fig 8: Measuring Resistance Of Motor Cable

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   NOTE:

   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

   Tester Connection	Switch Condition	Specified Condition
   U2-1 (W) - Body ground and shield ground	Power switch off	1 MΩ or higher
   U2-2 (U) - Body ground and shield ground	Power switch off	1 MΩ or higher
   U2-3 (V) - Body ground and shield ground	Power switch off	1 MΩ or higher

   TEXT IN ILLUSTRATION
   
   

   *1	Motor Cable

   HINT: 

   Perform this inspection while the motor cable are connected.

4. Install the upper inverter cover sub-assembly to the inverter with converter assembly.

NG → See step   18 

OK: Go to next step 

1. Check that the service plug grip is not installed.
   NOTE:

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

2. Check for arc marks on the AMD terminal.
   Fig 9: Identifying AMD Terminal

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Check that the bolt for the AMD terminal is tightened to the specified torque, the AMD terminal is connected securely, and there is no contact problem.

   Specified Condition

   7.6 N*m (77 kgf*cm, 67 in.*lbf)

   Result

   Result		Proceed to
   There are no arc marks.	The terminal is connected securely and there is no contact problem.	A
   There are no arc marks.	The terminal is not connected securely and there is a contact problem.	B
   There are arc marks.	-	C

B → CONNECT SECURELY 

C → REPLACE MALFUNCTIONING PARTS 

A: Go to next step 

1. Connect the cable to the negative (-) auxiliary battery terminal.
2. Measure the voltage according to the value(s) in the table below.
   Fig 10: Measuring Voltage Of AMD Terminal

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   B1-1 - Body ground	Power switch off	11 to 14 V

3. Disconnect the cable from the negative (-) auxiliary battery terminal.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Check that the service plug grip is not installed.
   NOTE:

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

2. Disconnect the inverter with converter assembly connector.
3. Connect the cable to the negative (-) auxiliary battery terminal.
4. Measure the voltage according to the value(s) in the table below.
   Fig 11: Measuring Voltage Of Inverter With Converter Assembly Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   A21-11 (S) - Body ground	Always	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector (to Inverter with Converter Assembly)

5. Turn the power switch on (IG).
6. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   A21-1 (IGCT) - Body ground	Power switch on (IG)	11 to 14 V

   NOTE:

   Turning the power switch on (IG) with the inverter with converter assembly connector disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

7. Turn the power switch off.
8. Disconnect the cable from the negative (-) auxiliary battery terminal.
9. Reconnect the inverter with converter assembly connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Check that the service plug grip is not installed.
   NOTE:

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

2. Disconnect the inverter with converter assembly connector.
3. Measure the resistance according to the value(s) in the table below.
   Fig 12: Measuring Resistance Of Inverter With Converter Assembly Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Resistance

   Tester Connection	Switch Condition	Specified Condition
   A21-12 (NODD) - Body ground	Power switch off	110 to 150 kΩ

   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector (to Inverter with Converter Assembly)

4. Reconnect the inverter with converter assembly connector.

NG → See step   19 

OK: Go to next step 

1. Connect the AC/DC 400 A probe to the positive auxiliary battery line.
2. Install the service plug grip.
3. Connect the cable to the negative (-) auxiliary battery terminal.
4. Turn the power switch on (READY) and leave the vehicle as it is until the electric current flowing into the auxiliary battery becomes 10 A or less.
   Fig 13: Identifying Probe Direction On AMD Line

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   TEXT IN ILLUSTRATION
   
   

   *a	Probe Direction
   *b	Current
   *c	AMD Line

5. Turn the power switch on (READY) and the headlight switch in the HI position, blower motor switch in the HI position, and the rear window defogger turned on.
6. Measure the current and voltage according to the value(s) in the table below.

   Standard

   Item	Tester Connection	Switch Condition	Specified Condition
   Current flowing from auxiliary battery	Auxiliary battery positive cable	Power switch on (READY) (The headlight position switch and blower motor switch are in the HI position, and the rear window defogger is turned on.)	30 A or higher
   Auxiliary battery voltage	Auxiliary battery positive (+) terminal - Auxiliary battery negative (-) terminal		13 to 15 V

7. Turn the power switch off.
8. Disconnect the cable from the negative (-) auxiliary battery terminal.

NG → See step   34 

OK: Go to next step 

B → ADD EV COOLANT 

C → REPEAIR FOR COOLANT LEAK AND ADD COOLANT 

A: Go to next step 

NG → CORRECT THE PROBLEM 

OK: Go to next step 

NG → See step   35 

OK: Go to next step 

1. Connect the Techstream to the DLC3.
2. Turn the power switch on (IG).
3. Enter the following menus: Powertrain / EV / Trouble Codes.
4. Read the freeze frame data Ambient Temperature using the Techstream.
5. Check if the freeze frame data Ambient Temperature is below freezing.

   Result

   Result	Proceed to
   Ambient Temperature value is above freezing temperature of the EV coolant.	A
   Ambient Temperature value is below freezing temperature of the EV coolant.	B

   HINT: 

   • EV coolant (SLLC) with a 30% concentration freezes at -15 °C (5°F) and EV coolant (SLLC) with a 50% concentration freezes at -35°C (-31°F).
   • If the EV coolant freezes in the EV radiator or EV water pump, the coolant temperature in the inverter with converter assembly rises because the EV coolant cannot circulate. As a result, a DTC may be set.
   • A DTC is set when the water pump impeller cannot rotate due to freezing of the EV coolant.
   • If a DTC is set due to freezing of EV coolant, the problem cannot be reproduced. Judge whether freezing of EV coolant occurred according to the freeze point of the EV coolant, EV coolant change history and ambient temperature when the DTC was set.
6. Turn the power switch off.

B → See step   20 

A → See step   34 

1. Check that the service plug grip is not installed.
   NOTE:

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

2. Remove the upper inverter cover sub-assembly from the inverter with converter assembly.
   Fig 14: Identifying Upper Inverter Cover Sub-Assembly Bolts

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Disconnect the motor cable from the inverter with converter assembly.
   Fig 15: Identifying Motor Cable On Inverter With Converter Assembly

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   TEXT IN ILLUSTRATION
   
   

   *1	Motor Cable (Inverter with Converter Assembly Side)

4. Using a megohmmeter set to 500 V, measure the insulation resistance according to the value(s) in the table below.
   Fig 16: Measuring Resistance Of Motor Cable (Inverter With Converter Assembly Side) Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   NOTE:

   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

   Tester Connection	Switch Condition	Specified Condition
   U2-1 (W) - Body ground and shield ground	Power switch off	100 MΩ or higher
   U2-2 (U) - Body ground and shield ground	Power switch off	100 MΩ or higher
   U2-3 (V) - Body ground and shield ground	Power switch off	100 MΩ or higher

   TEXT IN ILLUSTRATION
   
   

   *1	Motor Cable (Inverter with Converter Assembly Side)
   *2	Shield Ground

5. Connect the motor cable to the inverter with converter assembly.
6. Install the upper inverter cover sub-assembly to the inverter with converter assembly.

NG → See step   21 

OK → See step   34 

1. Disconnect all the connectors from the power management control ECU.
2. Measure the resistance according to the value(s) in the table below.
   Fig 17: Measuring Resistance Of Power Management Control ECU Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Resistance

   Tester Connection	Switch Condition	Specified Condition
   A23-15 (NODD) - C21-24 (E1)	Power switch off	110 to 150 kΩ

   TEXT IN ILLUSTRATION
   
   

   *a	Component without harness connected (Power Management Control ECU)

3. Reconnect the power management control ECU connectors.

NG → See step   31 

OK → REPAIR OR REPLACE HARNESS OR CONNECTOR 

NEXT → END 

B → REPLACE MALFUNCTIONING PARTS 

C → CONNECT SECURELY 

A: Go to next step 

NG → See step   36 

OK → See step   33 

1. Check that the service plug grip is not installed.
   NOTE:

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

2. Disconnect the inverter with converter assembly connector.
3. Remove the IGCT NO. 2 fuse from the No. 2 motor compartment relay block.
   Fig 18: Identifying IGCT No. 2 Fuse On No. 2 Motor Compartment Relay Block

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   TEXT IN ILLUSTRATION
   
   

   *1	No. 2 Motor Compartment Relay Block
   *2	IGCT NO. 2 Fuse

4. Measure the resistance according to the value(s) in the table below.
   Fig 19: Identifying IGCT NO. 2 Fuse On No. 2 Motor Compartment Relay Block & Inverter With Converter Assembly Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   TEXT IN ILLUSTRATION
   
   

   *1	No. 2 Motor Compartment Relay Block	*2	IGCT NO. 2 Fuse
   *a	Front view of wire harness connector (to Inverter with Converter Assembly)	-	-

   Standard Resistance

   Tester Connection	Switch Condition	Specified Condition
   A21-1 (IGCT) or 2 (IGCT NO. 2 fuse) - Body ground and other terminals	Power switch off	10 kΩ or higher

5. Install the IGCT NO. 2 fuse.
6. Reconnect the inverter with converter assembly connector.

NG → See step   28 

OK: Go to next step 

Refer to COMPONENTS

NEXT → REPLACE FUSE (IGCT NO. 2) 

1. Check that the service plug grip is not installed.
   NOTE:

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

2. Disconnect the inverter with converter assembly connector.
3. Remove the DCDC-S fuse from the No. 1 motor compartment relay block.
   Fig 20: Identifying DCDC-S Fuse On No. 1 Motor Compartment Relay Block

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   TEXT IN ILLUSTRATION
   
   

   *1	No. 1 Motor Compartment Relay Block
   *2	DCDC-S Fuse

4. Measure the resistance according to the value(s) in the table below.
   Fig 21: Identifying DCDC-S Fuse On No. 1 Motor Compartment Relay Block & Inverter with Converter Assembly Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   TEXT IN ILLUSTRATION
   
   

   *1	No. 1 Motor Compartment Relay Block	*2	DCDC-S Fuse
   *a	Front view of wire harness connector (to Inverter with Converter Assembly)	-	-

   Standard Resistance

   Tester Connection	Switch Condition	Specified Condition
   A21-11 (S) or 2 (DCDC-S fuse) - Body ground and other terminals	Power switch off	10 kΩ or higher

5. Install the DCDC-S fuse.
6. Reconnect the inverter with converter assembly connector.

NG → See step   29 

OK: Go to next step 

Refer to COMPONENTS

NEXT → REPLACE FUSE (DCDC-S) 

1. Remove the IGCT fuse from the No. 1 motor compartment relay block.
2. Remove the IGCT relay and IGCT NO. 2 fuse from the No. 2 motor compartment relay block.
   Fig 22: Identifying IGCT Fuse On No. 1 Motor Compartment Relay Block & IGCT No. 2 Fuse & IGCT Relay On No. 2 Motor Compartment Relay Block

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   TEXT IN ILLUSTRATION
   
   

   *1	No. 1 Motor Compartment Relay Block	*2	IGCT Fuse
   *3	No. 2 Motor Compartment Relay Block	*4	IGCT NO. 2 Fuse
   *5	IGCT Relay	-	-

3. Measure the resistance according to the value(s) in the table below.
   Fig 23: Identifying IGCT Relay On No. 2 Motor Compartment Relay Block

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Resistance

   Tester Connection	Switch Condition	Specified Condition
   3 (IGCT relay) - Body ground and other terminals	Always	10 kΩ or higher
   5 (IGCT relay) - Body ground and other terminals	Always	10 kΩ or higher

   TEXT IN ILLUSTRATION
   
   

   *1	No. 2 Motor Compartment Relay Block
   *2	IGCT Relay

4. Install the IGCT relay, IGCT fuse and IGCT NO. 2 fuse.

NG → See step   30 

OK → REPLACE FUSE (IGCT) 

NEXT → REPLACE FUSE (IGCT NO. 2) 

NEXT → REPLACE FUSE (DCDC-S) 

NEXT → REPLACE FUSE (IGCT) 

1. Even though it has been determined that the power management control ECU needs to be replaced, make sure to inspect the voltage difference between No. 1 EV battery and No. 2 EV battery before replacing it.

NEXT → See step   37