DTC P0A93-346: Inverter Cooling System Performance [08/2013 - ]: Procedure

WARNING: This page is about a different car, the 2014 Lexus ES 300h. However, it is still accessible from the selected car via links, so may be relevant.

CHECK VEHICLE CONDITION

Make sure that the front side of the radiator grille is not blocked with anything.

Ask the customer if the front side of the radiator grille was blocked with anything.

Result

Result	Proceed to
Not blocked.	A
Is/was blocked.	B

HINT:

If the radiator grille is blocked, the inverter coolant temperature will increase and this DTC may be stored.

B → IF EQUIPPED, EXPLAIN TO CUSTOMER THAT OPTIONAL COVER WILL BE REMOVED

A: Go to next step

CHECK DTC OUTPUT (HYBRID CONTROL)

Connect the Techstream to the DLC3.
Turn the power switch on (IG).
Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.

Check for DTCs.

Result

Result	Proceed to
P0A93-346 only is output, or DTCs except the ones in the table below are also output.	A
Any of the following DTCs are also output.	B

DTC No.	Relevant Diagnosis
P0A02-719	Motor Electronics Coolant Temperature Sensor Circuit Low
P0A03-720	Motor Electronics Coolant Temperature Sensor Circuit High
P0C73-776	Motor Electronics Coolant Pump "A" Control Performance
P314A-828	Inverter Coolant Pump Speed Signal

HINT:

P0A93-346 may be stored due to a malfunction which also causes DTCs in the preceding table to be stored. In this case, first troubleshoot the output DTCs in the preceding table. Then, perform a test to attempt to reproduce the problems, and check that no DTCs are output.

Turn the power switch off.

B → See step 12

A: Go to next step

CHECK CONNECTOR CONNECTION CONDITION (INVERTER WITH CONVERTER ASSEMBLY CONNECTOR). Refer to PROCEDURE - Step 4
NG → CONNECT SECURELY

OK: Go to next step
CHECK QUANTITY OF HV COOLANT. Refer to PROCEDURE - Step 3
B → ADD HV COOLANT

C → INSPECT FOR HV COOLANT LEAK AND ADD HV COOLANT

A: Go to next step
CHECK COOLANT HOSE. Refer to PROCEDURE - Step 4
NG → CORRECT THE PROBLEM

OK: Go to next step
PERFORM ACTIVE TEST USING TECHSTREAM (CONTROL THE ELECTRIC COOLING FAN). Refer to PROCEDURE - Step 5
NG → See step 13

OK: Go to next step

READ VALUE USING TECHSTREAM (DATA LIST)

Turn the power switch off and leave the vehicle for at least 1 hour.
Connect the Techstream to the DLC3.
Turn the power switch on (IG).
Enter the following menus: Powertrain / Hybrid Control / Data List / Inverter Coolant Water Temperature, Inverter Temp (MG2), Cnv Tmp (Upper), Cnv Temp (Lower), Inverter Temp (MG1).

Read the Data List.

Result

Result	Proceed to
Other than below.	A
"Inverter Coolant Water Temperature" value is higher than the displayed temperature of any other Data List item by 20°C (68°F) or more.	B

NOTE:

The lower limit temperature that can be displayed for "Inverter Temp (MG1)", "Inverter Temp (MG2)", "Cnv Tmp (Upper)" and "Cnv Temp (Lower)" is 15°C (59°F). The lower limit temperature for "Inverter Coolant Water Temperature" is -40°C (-40°F). The "Inverter Coolant Water Temperature" value displayed on the Techstream may be lower than the others, but this is not a malfunction.

Turn the power switch off.

B → See step 11

A: Go to next step

CHECK HV COOLANT (CHECK FOR CONDITIONS THAT MAY HAVE CAUSED FREEZING). Refer to PROCEDURE - Step 6
B → See step 10

A: Go to next step
REPLACE HV COOLANT. Refer to PROCEDURE - Step 7
NEXT → COMPLETED
REPLACE INVERTER WATER PUMP ASSEMBLY. Refer to COMPONENTS [08/2013 - ]
REPLACE INVERTER WITH CONVERTER ASSEMBLY. Refer to COMPONENTS [08/2013 - ]
GO TO DTC CHART (HYBRID CONTROL SYSTEM). Refer to DIAGNOSTIC TROUBLE CODE CHART [08/2013 - ]
CHECK COOLING FAN SYSTEM. Refer to Cooling Fan Circuit [08/2013 - ]