DTC P0A93-346: Inverter Cooling System Performance: Procedure

1. Connect the Techstream to the DLC3.
2. Turn the power switch on (IG).
3. Select the following menu items: Powertrain / Hybrid Control / Trouble Codes.
4. Check if DTCs are output.

   Result

   DTC No.	Relevant Diagnosis
   P0A02-719, P0A03-720	Inverter coolant temperature circuit
   P0A1D (all INF codes) *1	Hybrid Powertrain Control Module
   P0A1B (all INF codes) *1	Drive Motor "A" Control Module

   HINT: 

   • *1: If any INF codes are output for this DTC, refer to the corresponding diagnostic flowchart above.
   • Turning the power switch on (IG) with the service plug grip and inverter cover removed causes interlock switch system DTC P0A0D-350 to be output.
   • P0A93-346 may be output due to a malfunction which causes the DTCs in the table above to be output. In this case, first troubleshoot the output DTCs in the table above. Then, perform a reproduction test to check that no DTCs are output.

YES → GO TO  DIAGNOSTIC TROUBLE CODE CHART  DTC CHART 

NO: Go to next step 

NG → CONNECT SECURELY 

OK: Go to next step 

1. Check for coolant leaks.
2. Check the coolant in the water reserve tank assembly is above the low level.

   Result

   Result	Proceed to
   Coolant leaks are not evident. The coolant level in the water reserve tank assembly is above the low level.	A
   Coolant leaks are not evident. The coolant level in the water reserve tank assembly is below the low level.	B
   Coolant leaks are evident.	C

   HINT: 

   After repairing the coolant leaks and adding coolant, perform the WATER PUMP and COOLING FAN SPD active tests and make sure that there are no malfunctions.

B → ADD COOLANT 

C → FIX COOLANT LEAKS AND ADD COOLANT 

A: Go to next step 

1. Check if the hoses of the cooling system are kinked or clogged.
   Fig 1: Identifying Cooling System Components

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG → CORRECT THE PROBLEM 

OK: Go to next step 

1. Connect the Techstream to the DLC3.
2. Turn the power switch on (IG).
3. Select the following menu items: Powertrain / Hybrid Control / Active Test / Activate the Water Pump.
4. Perform the "Activate the Water Pump" active test.
5. During the "Activate the Water Pump" active test, open the water reserve tank cap and check that there are ripples in the coolant. Continue the active test for at least 1 minute.

   Result

   There are ripples in the coolant in the water reserve tank assembly for 1 minute.

   HINT: 

   The water pump motor operates even in inspection mode.

NG → See step   9 

OK: Go to next step 

1. Connect the Techstream to the DLC3.
2. Turn the power switch on (IG).
3. Select the following menu items: Powertrain / Engine and ECT / Active Test / Control the Electric Cooling Fan.
4. Perform the "Control the Electric Cooling Fan" active test.

   OK

   The cooling fan rotates.

NG → See step   8 

OK: Go to next step 

1. Stop the engine and leave the vehicle for at least 1 hour.
2. Connect the Techstream to the DLC3.
3. Turn the power switch on (IG).
4. Select the following menu items: Powertrain / Hybrid Control / Data List / Inverter Coolant Water Temperature, Inverter Temp-(MG2), Converter Temperature, Inverter Temp-(MG1).
5. Read the data list.

   NG

   The displayed "Inverter Coolant Water Temperature" value is at least 20°C (68°F) higher than "Inverter Temp-(MG2), Converter Temperature, and Inverter Temp-(MG1)".

   NOTE:

   The lower limit temperature that can be displayed for "Inverter Temp-(MG2), Converter Temperature, and Inverter Temp-(MG1)" is 15°C (59°F). The lower limit temperature for "Inverter Coolant Water Temperature" is -50°C (-58°F). The "Inverter Coolant Water Temperature" value displayed on the Techstream may be lower than the others, but this is not a malfunction.

OK → See step   25 

NG → See step   26 

1. Check the connections of the cooling fan motor connectors.
   Fig 2: Identifying Connections Of Cooling Fan Motor Connectors Location

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   OK

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

NG → CONNECT SECURELY 

OK → See step   27 

1. Connect the Techstream to the DLC3.
2. Compress the inlet hose for the water pump with motor & bracket assembly several times.
3. Turn the power switch on (IG).
4. Select the following menu items: Powertrain / Hybrid Control / Active Test / Activate the Water Pump.
5. Perform the "Activate the Water Pump" active test.
6. During the "Activate the Water Pump" active test, open the water reserve tank cap and check that there are ripples in the coolant. Continue the active test for at least 1 minute.

   Result

   There are ripples in the coolant in the water reserve tank assembly for 1 minute.

   HINT: 

   • Keep compressing the water pump inlet hose until the coolant level in the water reserve tank assembly stops dropping.
   • The water pump motor operates even in maintenance mode.
   • After repairing the coolant leaks and adding coolant, perform the WATER PUMP and COOLING FAN SPD active tests and make sure that there are no malfunctions.

OK → ADD COOLANT 

NG: Go to next step 

1. Remove the INV W/P fuse from the engine room R/B.
   Fig 3: Identifying INV W/P Fuse Terminal Location

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

   Standard resistance

   Tester Connection	Specified Condition
   INV W/P fuse terminal	Below 1 Ω

3. Install the INV W/P fuse.

NG → See step   16 

OK: Go to next step 

1. Remove the INV W/P fuse from the engine room R/B.
   Fig 4: Identifying INV W/P Fuse And IGCT Relay Location

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Remove the IGCT relay from the engine room R/B.
3. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Tester Connection	Specified Condition
   INV W/P fuse 1 - IGCT relay 3	Below 1 Ω

NG → REPAIR OR REPLACE ENGINE ROOM R/B 

OK: Go to next step 

1. Check the connection of the water pump with motor & bracket assembly connector.
   Fig 5: Identifying Water Pump With Motor Bracket Assembly Connector Location

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   OK

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

NG → CONNECT SECURELY 

OK: Go to next step 

NG → CONNECT SECURELY 

OK: Go to next step 

1. Remove the INV W/P fuse from the engine room R/B.
2. Measure the resistance according to the value(s) in the table below.
   Fig 6: Identifying Connector Terminal Identification (Water Pump With Motor Power Source Circuit)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard resistance (Check for open)

   Tester Connection	Specified Condition
   IWP (A61-52) - SWP (A65-3)	Below 1 Ω
   GND (A65-1) - Body ground	Below 1 Ω
   Engine room R/B INV W/P fuse terminal 2 - +BWP (A65-4)	Below 1 Ω

   Standard resistance (Check for short)

   Tester Connection	Specified Condition
   IWP (A61-52) or SWP (A65-3) - Body ground	10 kΩ or more
   Engine room R/B INV W/P fuse terminal 2 or +BWP (A65-4) - Body ground	10 kΩ or more

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Disconnect the A61 hybrid vehicle control ECU connector.
   Fig 7: Identifying INV W/P Fuse Location

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Remove the INV W/P fuse from the engine room R/B.
3. Apply 12 V to terminal 2 of the socket for the fuse in the engine room R/B and check that the water pump operates.

   OK

   The water pump operates.

4. Install the INV W/P fuse to the engine room R/B.

NG → See step   25 

OK → See step   28 

1. Check the connection of the water pump with motor & bracket assembly connector.
   Fig 8: Identifying Water Pump With Motor Bracket Assembly Connector Location

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   OK

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

NG → See step   21 

OK: Go to next step 

NG → See step   22 

OK: Go to next step 

1. Remove the INV W/P fuse from the engine room R/B.
2. Measure the resistance according to the value(s) in the table below.
   Fig 9: Identifying Connector Terminal Connector Identification (Water Pump With Motor Power Source Circuit)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard resistance (Check for open)

   Tester Connection	Specified Condition
   IWP (A61-52) - SWP (A65-3)	Below 1 Ω
   GND (A65-1) - Body ground	Below 1 Ω
   Engine room R/B INV W/P fuse terminal 2 - +BWP (A65-4)	Below 1 Ω

   Standard resistance (Check for short)

   Tester Connection	Specified Condition
   IWP (A61-52) or SWP (A65-3) - Body ground	10 kΩ or more
   Engine room R/B INV W/P fuse terminal 2 or +BWP (A65-4) - Body ground	10 kΩ or more

NG → See step   23 

OK: Go to next step 

1. Disconnect the A61 hybrid vehicle control ECU connector.
   Fig 10: Identifying INV W/P Fuse Location

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Remove the INV W/P fuse from the engine room R/B.
3. Apply 12 V to terminal 2 of the socket for the fuse in the engine room R/B and check that the water pump operates.

   OK

   The water pump operates.

4. Install the INV W/P fuse to the engine room R/B.

NG → See step   24 

OK: Go to next step 

1. Replace the hybrid vehicle control ECU. Refer to REMOVAL

NEXT → REPLACE FUSE (INV W/P) 

1. Securely connect the water pump with motor & bracket assembly connector.

NEXT → REPLACE FUSE (INV W/P) 

1. Securely connect the hybrid vehicle control ECU connectors.

NEXT → REPLACE FUSE (INV W/P) 

1. Repair or replace the harness or connector.

NEXT → REPLACE FUSE (INV W/P) 

1. Replace the water pump with motor & bracket assembly. Refer to REMOVAL

NEXT → REPLACE FUSE (INV W/P)