Inspection Procedure

WARNING: This page is about a different car, the 2006 Lexus RX 400h. However, it is still accessible from the selected car via links, so may be relevant.

CAUTION:

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.

READ OUTPUT DTC (HV)

Connect the intelligent tester to the DLC3.
Turn the ignition switch to the ON position.
Select the following menu items: DIAGNOSIS / OBD/ MOBD / HV ECU / DTC INFO / CURRENT CODES.

Read output DTCs. (See DTC CHECK / CLEAR )

Result:

The DTCs shown in the table below are output

OUTPUT DTC (HV)

DTC No.	Relevant Diagnosis
P0A94-547, 548, 549	Boost converter circuit
P0AA6-526, 613, 655	High-voltage insulation problem detection circuit
P0AA2-227, P0AA5-229	SMR circuit
P3004-131, 803	High-voltage system
P0A93-346, 347, P0A05-776	Inverter cooling system

YES: GO TO DIAGNOSTIC TROUBLE CODE CHART

NO: GO TO NEXT STEP

CHECK RELAY BLOCK ASSEMBLY
1. Check the installation of the fusible links (DC/DC and MAIN) and fuse (DC/DC-S) in the relay block. Check if the circuits are open.
  OK:
  
  They are connected securely. There are no open circuits in the fuse or fusible links.
NG: REPLACE FUSIBLE LINK OR FUSE, OR REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: GO TO NEXT STEP
CHECK CONNECTION CONDITION OF HYBRID VEHICLE CONTROL ECU CONNECTOR (LOOSENESS AND POOR CONTACT)
1. Check the connections of all HV control ECU connectors.
  OK:
  
  Connectors are connected securely and there is no poor connection.
Fig 1: Checking Connection Condition Of Hybrid Vehicle Control ECU Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: CONNECT SECURELY

OK: GO TO NEXT STEP
CHECK CONNECTION CONDITION OF MG ECU CONNECTOR (LOOSENESS AND POOR CONTACT)
CAUTION: Be sure to wear insulated gloves.
1. Turn the ignition switch off and remove the service plug grip. (See PRECAUTION )
  NOTE: Do not put the vehicle into the READY-on state with the service plug grip removed as this may cause a malfunction.
2. 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.
  - 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.
3. Check the connections of the MG ECU connectors.
  Standard:
  
  Connectors are connected securely and there is no poor connection.
Fig 2: Checking Connection Condition Of MG ECU Connector (Looseness And Poor Contact)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: CONNECT SECURELY

OK: GO TO NEXT STEP

CHECK INSULATION RESISTANCE OF HIGH-VOLTAGE SYSTEM

CAUTION: Be sure to wear insulated gloves.

Check that the service plug grip is removed.

Using a megohmmeter, measure the insulation resistance according to the value(s) in the table below.

Standard Resistance

INSULATION RESISTANCE OF HIGH-VOLTAGE SYSTEM

Tester Connection	Specified Condition
Three-phase AC Cable for Motor U - Body ground and shielded wire ground	1 MΩ or higher
Three-phase AC Cable for Motor V - Body ground and shielded wire ground	1 MΩ or higher
Three-phase AC Cable for Motor W - Body ground and shielded wire ground	1 MΩ or higher

HINT:

Perform this inspection with the three-phase AC cable of the Motor connected.

Fig 3: Checking Insulation Resistance Of High-Voltage System

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: Go to step 11

OK: GO TO NEXT STEP

CHECK CONNECTION OF AMD TERMINAL
CAUTION: Be sure to wear insulated gloves.
1. Check that the service plug grip is removed.
  
  Fig 4: Identifying Rear Traction Motor W/Transaxle Assembly
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Remove the three-phase AC cable for the Rear Motor from the w/ converter inverter assembly.
3. Check the connection of the AMD terminal.
  OK:
  
  Terminal is connected securely and there is no poor connection.
Fig 5: Identifying Three-Phase AC Cable For Rear Motor
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: Go to step 13

OK: GO TO NEXT STEP

CHECK AMD TERMINAL VOLTAGE (W/ CONVERTER INVERTER ASSEMBLY SIDE)

CAUTION: Be sure to wear insulated gloves.

Turn the ignition switch off.
Check that the service plug grip is removed.

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

Standard Voltage

AMD TERMINAL VOLTAGE (W/ CONVERTER INVERTER ASSEMBLY SIDE)

Tester Connection	Specified Condition
AMD terminal (w/ converter inverter assembly side) - Body ground	10 to 14 V

Fig 6: Checking AMD Terminal Voltage (W/Converter Inverter Assembly Side)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: Go to step 19

OK: GO TO NEXT STEP

INSPECT MG ECU

CAUTION: Be sure to wear insulated gloves.

Check that the service plug grip is removed.
Turn the ignition switch to the ON position.
NOTE: Do not put the vehicle into the READY-on state with the service plug grip removed as this may cause a malfunction.

HINT:

Turning the ignition switch to the ON position with the service grip and inverter cover removed causes interlock switch system DTC P0A0D-350 to be output.

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

Standard Voltage

MG ECU

Tester Connection	Specified Condition
+B (I21-7) - Body ground	10 to 14 V
+B2 (I21-4) - Body ground	10 to 14 V
SI (I21-35) - Body ground	10 to 14 V

Fig 7: Inspecting MG ECU

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: GO TO NEXT STEP

CHECK HARNESS AND CONNECTOR (RESISTANCE VALUE OF NODD INSIDE HV CONTROL ECU)

Turn the ignition switch off.
Disconnect the I21 connector from the MG ECU.

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

Standard Resistance

RESISTANCE VALUE OF NODD INSIDE HV CONTROL ECU

Tester Connection	Specified Condition
NODD (I21-33) - Body ground	120 to 140 kΩ

Fig 8: Checking Harness And Connector (Resistance Value Of NODD Inside HV Control ECU)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: Go to step 20

OK: GO TO NEXT STEP

CHECK OPERATION DC/DC CONVERTER

HINT:

The current at the AMD terminal cannot be measured directly because of space limitations. Measure the current flowing from the auxiliary battery instead.

Connect the AC/DC 400 A probe to the positive auxiliary battery line.
Install the inverter cover. (See INVERTER WITH CONVERTER )
Install the service plug grip.
Put the vehicle into the READY-on state and leave the vehicle as it is until the electric current flowing into the auxiliary battery becomes 10 A or less.

Fig 9: Checking Operation DC/DC Converter (1 Of 2)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Measure the current flowing from the auxiliary battery with the headlight position switch and blower motor switch in the HI position, and the rear window defogger turned on. (*1)

Measure the auxiliary battery voltage according to the previous conditions (*1).

Standard Current and Voltage

OPERATION DC/DC CONVERTER

Measurement Item	Specified Condition
Current flowing from auxiliary battery	0 A or less (no current from auxiliary battery)
Auxiliary battery voltage	13 to 15 V

Fig 10: Checking Operation DC/DC Converter (2 Of 2)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: Go to step 14

NG: REPLACE W/ CONVERTER INVERTER ASSEMBLY

INSPECT HYBRID VEHICLE TRANSAXLE ASSEMBLY (MOTOR AND GENERATOR)

CAUTION: Be sure to wear insulated gloves.

Check that the service plug grip is removed.
Disconnect the three-phase AC cables of the HV transaxle assembly (Motor and Generator) from the w/ converter inverter assembly.

Fig 11: Identifying Hybrid Vehicle Transaxle Assembly (Motor And Generator)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Using a megohmmeter, measure the insulation resistance according to the value(s) in the table below.

Standard Resistance

HYBRID VEHICLE TRANSAXLE ASSEMBLY (MOTOR AND GENERATOR)

Tester Connection	Specified Condition
Three-phase AC cable for Motor U terminal - Body ground and shielded wire ground	10 MΩ or higher
Three-phase AC cable for Motor V terminal - Body ground and shielded wire ground	10 MΩ or higher
Three-phase AC cable for Motor W terminal - Body ground and shielded wire ground	10 MΩ or higher
Three-phase AC cable for Generator U terminal - Body ground and shielded wire ground	10 MΩ or higher
Three-phase AC cable for Generator V terminal - Body ground and shielded wire ground	10 MΩ or higher
Three-phase AC cable for Generator W terminal - Body ground and shielded wire ground	10 MΩ or higher

Fig 12: Measuring Insulation Resistance

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY

OK: GO TO NEXT STEP

INSPECT REAR TRACTION MOTOR W/TRANSAXLE ASSEMBLY

CAUTION: Be sure to wear insulated gloves.

Check that the service plug grip is removed.
Disconnect the three-phase AC cable for the Rear Motor from the w/ converter inverter assembly.

Fig 13: Inspecting Rear Traction Motor W/Transaxle Assembly
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Using a megohmmeter, measure the insulation resistance according to the value(s) in the table below.

Standard Resistance

REAR TRACTION MOTOR W/TRANSAXLE ASSEMBLY

Tester Connection	Specified Condition
Three-phase AC cable for Rear Motor U terminal - Body ground and shielded wire ground	10 MΩ or higher
Three-phase AC cable for Rear Motor V terminal - Body ground and shielded wire ground	10 MΩ or higher
Three-phase AC cable for Rear Motor W terminal - Body ground and shielded wire ground	10 MΩ or higher

Fig 14: Inspecting Rear Traction Motor W/Transaxle Assembly

NG: Go to step 21

OK: REPLACE W/ CONVERTER INVERTER ASSEMBLY

CHECK AMD TERMINAL
CAUTION: Be sure to wear insulated gloves.
1. Check for ark marks on the AMD terminals (w/ converter inverter assembly side and wire harness side).
  OK:
  
  There are no ark marks.
  
  HINT:
  
  The wire harness between the AMD terminal on the w/ converter inverter assembly side and the AMD terminal on the vehicle side is supplied with the w/ converter inverter assembly as a unit. If the wire harness is faulty, replace the w/ converter inverter assembly.
Fig 15: Identifying AMD Terminals
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE W/ CONVERTER INVERTER ASSEMBLY

OK: CONNECT SECURELY
CHECK QUANTITY OF HV COOLANT
1. Check the inverter coolant level.
  OK:
  
  There is sufficient amount of coolant for the inverter.
NG: CHECK FOR COOLANT LEAKS AND ADD COOLANT

OK: GO TO NEXT STEP
CHECK COOLANT HOSE
1. Check if the hoses of the cooling system are not bent or clogged.
  OK:
  
  The hoses of the cooling system are not bent or clogged.
Fig 16: Checking Coolant Hose
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: CORRECT TO NORMAL CONDITION

OK: GO TO NEXT STEP
CHECK CONNECTION CONDITION OF WATER PUMP CONNECTOR (LOOSENESS AND POOR CONTACT)
1. Check the connection of the water pump w/ motor & bracket assembly connector.
  OK:
  
  Connector is connected securely and there is no poor connection.
Fig 17: Checking Connection Condition Of Water Pump Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: CONNECT SECURELY

OK: GO TO NEXT STEP
PERFORM ACTIVE TEST BY INTELLIGENT TESTER (WATER PUMP)
1. Connect the intelligent tester to the DLC3.
2. Turn the ignition switch to the ON position.
3. Select the following menu items: DIAGNOSIS / OBD/ MOBD / HV ECU / ACTIVE TEST / WATER PUMP.
4. During the WATER PUMP active test, check operation of the water pump.
  OK:
  
  There are ripples in the reservoir tank coolant.
  
  HINT:
  
  The water pump is also activated in the READY-on state.
NG: INSPECT WATER PUMP W/ MOTOR & BRACKET ASSEMBLY CIRCUIT

OK: GO TO NEXT STEP
PERFORM ACTIVE TEST BY INTELLIGENT TESTER (COOLING FAN)
1. Connect the intelligent tester to the DLC3.
2. Turn the ignition switch to the ON position.
3. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / ENGINE / ACTIVE TEST / COOLING FAN.
4. Perform the COOLING FAN active test.
  OK:
  
  Electrical cooling fan operate.
NG: INSPECT WATER PUMP W/ MOTOR & BRACKET ASSEMBLY CIRCUIT

OK: REPAIR OR REPLACE HARNESS OR CONNECTOR

CHECK AMD TERMINAL (VEHICLE SIDE)

Turn the ignition switch off.

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

Standard Voltage

AMD TERMINAL (VEHICLE SIDE)

Tester Connection	Specified Condition
AMD terminal - Body ground	10 to 14 V

Fig 18: Checking AMD Terminal (Vehicle Side)

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: REPLACE W/ CONVERTER INVERTER ASSEMBLY

INSPECT HYBRID VEHICLE CONTROL ECU

Turn the ignition switch off and disconnect all HV control ECU connectors.

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

Standard Resistance

HYBRID VEHICLE CONTROL ECU

Tester Connection	Specified Condition
NODD (H38-11) - E1 (H31-5)	120 to 140 kΩ

Fig 19: Inspecting Hybrid Vehicle Control ECU

NG: REPLACE HYBRID VEHICLE CONTROL ECU

OK: REPAIR OR REPLACE HARNESS OR CONNECTOR

INSPECT REAR TRACTION MOTOR W/TRANSAXLE ASSEMBLY

CAUTION:

Be sure to wear insulated gloves.

Check that the service plug grip is removed.
Disconnect the frame wire No. 3 (three-phase AC cable for Rear Motor) from the rear traction motor w/ transaxle assembly.

Fig 20: Identifying Frame Wire No. 3
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Using a megohmmeter, measure the insulation resistance according to the value(s) in the table below.

Standard Resistance

REAR TRACTION MOTOR W/TRANSAXLE ASSEMBLY

Tester Connection	Specified Condition
Three-phase AC cable for Rear Motor U terminal - Body ground and shielded wire ground	10 MΩ or higher
Three-phase AC cable for Rear Motor V terminal - Body ground and shielded wire ground	10 MΩ or higher
Three-phase AC cable for Rear Motor W terminal - Body ground and shielded wire ground	10 MΩ or higher

Fig 21: Measuring Insulation Resistance

NOTE: Wrap terminals U, V, and W of the frame wire No. 3 (three-phase AC cable for Rear Motor) on the w/ converter inverter assembly side with insulation tape to prevent the terminals from contacting the ground.

NG: REPLACE FRAME WIRE NO. 3

OK: REPLACE REAR TRACTION MOTOR W/TRANSAXLE ASSEMBLY