Inspection Procedure
- 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)
- Put the vehicle into the READY-on state and wait for 10 seconds or more.
- 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 DTC shown in the table below is output
DTCS RESULT DESCRIPTIONDTC No. Relevant Diagnosis P0A05-776 Water pump malfunction
YES: GO TO DTC CHART
NO: Go to next step
- CHECK QUANTITY OF COOLANT (FOR INVERTER)
- Check the coolant level.
OK: There is a sufficient amount of coolant.
NG: CHECK FOR COOLANT LEAKS AND ADD COOLANT (FOR INVERTER)
OK: Go to next step
- Check the coolant level.
- CHECK COOLANT HOSE
- 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.
NG: CORRECT TO NORMAL CONDITION
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
OK: Go to next step
- Check if the hoses of the cooling system are not bent or clogged.
- CHECK CONNECTION CONDITION OF WATER PUMP CONNECTOR (LOOSENESS AND POOR CONTACT)
- Check the connection of the water pump w/ motor connector.
OK: Connector is connected securely and there is no poor connection.
NG: CONNECT SECURELY
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
OK: Go to next step
- Check the connection of the water pump w/ motor connector.
- PERFORM ACTIVE TEST BY INTELLIGENT TESTER (WATER PUMP)
- 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 / ACTIVE TEST / WATER PUMP.
- 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: GO TO step 8
OK: Go to next step
- CHECK CONNECTION CONDITION OF COOLING FAN CONNECTOR (LOOSENESS AND POOR CONTACT)
- Check the connection of the electric cooling fan connector.
OK: Connector is connected securely and there is no poor connection.
NG: CONNECT SECURELY
OK: Go to next step
- Check the connection of the electric cooling fan connector.
- PERFORM ACTIVE TEST BY INTELLIGENT TESTER (COOLING FAN)
- Connect the intelligent tester to the DLC3.
- Turn the ignition switch to the ON position.
- Select the following menu items: DIAGNOSIS / ENHANCED OBD II / ENGINE /ACTIVE TEST/ COOLING FAN.
- During the COOLING FAN activate test, check operation of the electric cooling fan.
OK: The electric cooling fan operates.
NG: CHECK COOLING FAN CIRCUIT
OK: REPLACE W/ CONVERTER INVERTER ASSEMBLY
- CHECK HARNESS AND CONNECTOR (HV CONTROL ECU - WATER PUMP)
- Turn the ignition switch off.
- Disconnect the H29 connector from the HV control ECU.
- Disconnect the W5 water pump connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for open)
TESTER CONNECTION AND SPECIFIED CONDITIONTester Connection Specified Condition NIWP (H29-29) - NWP (W5-1) Below 1 Ω IWP (H29-23) - SWP (W5-2) Below 1 Ω Standard Resistance (Check for short)
TESTER CONNECTION AND SPECIFIED CONDITIONTester Connection Specified Condition NIWP (H29-29) or NWP (W5-1) - Body ground 10 kΩ or higher IWP (H29-23) or SWP (W5-2) - Body ground 10 kΩ or higher
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
OK: Go to next step
- CHECK HARNESS AND CONNECTOR (WATER PUMP - INV W/P FUSE, WATER PUMP BODY GROUND)
- Turn the ignition switch off.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for open)
TESTER CONNECTION AND SPECIFIED CONDITIONTester Connection Specified Condition +B (W5-4) - Engine Room R/B INV W/P fuse terminal 2 Below 1 Ω GND (W5-3) - Body ground Below 1 Ω Standard Resistance (Check for short)
TESTER CONNECTION AND SPECIFIED CONDITIONTester Connection Specified Condition +B (W5-4) or Engine Room R/B INV W/P fuse terminal 2 - Body ground 10 kΩ or higher
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: Go to next step
- CHECK HYBRID VEHICLE CONTROL ECU
- Connect the HV control ECU connector.
- Put the vehicle into the READY-on state.
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
TESTER CONNECTION AND SPECIFIED CONDITIONTester Connection Specified Condition IWP (H29-23) - Body ground Below 1 V
OK: GO TO step 12
NG: Go to next step
- INSPECT WATER PUMP W/ MOTOR & BRACKET ASSEMBLY
- Disconnect the H29 HV control ECU Connector.
- Turn the ignition switch to the ON position.
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
TESTER CONNECTION AND SPECIFIED CONDITIONTester Connection Specified Condition IWP (H29-23) - E1 (H31-5) 10 to 14 V
NG: REPLACE WATER PUMP W/ MOTOR & BRACKET ASSEMBLY
OK: REPLACE HYBRID VEHICLE CONTROL ECU
- INSPECT HYBRID VEHICLE CONTROL ECU
- Connect the HV control ECU connector.
- Put the vehicle into the READY-on state.
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
TESTER CONNECTION AND SPECIFIED CONDITIONTester Connection Specified Condition IWP (H29-23) - E1 (H31-5) 10 to 14 V
NG: REPLACE HYBRID VEHICLE CONTROL ECU
OK: REPLACE WATER PUMP W/ MOTOR & BRACKET ASSEMBLY