| DTC Code | DTC Name |
|---|---|
| P0A93-346 | Inverter Cooling System Performance |
DESCRIPTION
The inverter converts the high-voltage direct current of the HV battery into the alternating current for MG1 and MG2. The inverter generates heat during the conversion process. Therefore, the inverter is cooled by a special cooling system consisting of the inverter water pump assembly, the cooling fan, and a radiator. This cooling system is independent of the engine cooling system. The power management control ECU monitors the electric water pump, cooling fan, and cooling system, and detects the following malfunctions.
| *1 | Inverter Water Pump Assembly | *2 | Inverter Reserve Tank Assembly |
| *3 | Inverter with Converter Assembly | *4 | Radiator Assembly (HV) |
| *5 | Hybrid Vehicle Transaxle Assembly | - | - |
| DTC No. | INF Code | DTC Detection Condition | Trouble Area |
|---|---|---|---|
| P0A93 | 346 | HV cooling temperature increases and the temperature of any inverter with converter assembly related parts increases. (1 trip detection logic) |
|
| DTC No. | INF Code | Data List Item |
|---|---|---|
| P0A93 | 346 |
|
CAUTION / NOTICE / HINT
CAUTION:
Before inspecting the high-voltage system or disconnecting the low voltage connector of the inverter with converter assembly, take safety precautions such as wearing insulated gloves and removing the service plug grip to prevent electrical shocks. After removing the service plug grip, put it in your pocket to prevent other technicians from accidentally reconnecting it while you are working on the high-voltage system.
After removing the service plug grip, wait for at least 10 minutes before touching any of the high-voltage connectors or terminals. After waiting for 10 minutes, check the voltage at the terminals in the inspection point in the inverter with converter assembly. The voltage should be 0 V before beginning work Click here.
Tech Tips
Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.
Note
After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work Click here.
Tech Tips
After the repair, clear the DTCs and perform the following procedure to check that DTCs are not output.
Perform a road test according to the freeze frame data "Vehicle Spd" for approximately 15 minutes.
During the road test, check Data List items "Inverter Coolant Water Temperature", "Inverter Temp-(MG2)", "Inverter Temp- (MG1)", "DC/DC Cnv Temp (Upper)" and " DC/DC Cnv Temp (Lower)" to prevent them from overheating.
PROCEDURE
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 | ||||||
|---|---|---|---|---|---|---|
|
Tech Tips
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 |
|
CHECK DTC OUTPUT (HYBRID CONTROL)
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.
Check if DTCs are output.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| 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 |
Tech Tips
P0A93-346 may be set due to a malfunction which also causes DTCs in the preceding table to be set. 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 |
|
GO TO DTC CHART (HYBRID CONTROL SYSTEM) Click here |
| A |
|
CHECK CONNECTOR CONNECTION CONDITION (INVERTER WITH CONVERTER ASSEMBLY CONNECTOR)
CAUTION:
Be sure to wear insulated gloves.
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 manual 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.
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. |
Tech Tips
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 |
|
CHECK QUANTITY OF HV COOLANT
Check the coolant level in the inverter reserve tank.
Check for coolant leaks.
| Result | Proceed to |
|---|---|
| No leaks are found and coolant level in the inverter reserve tank assembly is above the low line. | A |
| No leaks are found and coolant level in the inverter reserve tank assembly is below the low line. | B |
| HV coolant leaks are evident. | C |
Tech Tips
After repairing the coolant leaks and adding coolant, perform the "Activate the Water Pump" Active Test (HV Active Test item) and the "Control the Electric Cooling Fan" Active Test (Engine Active Test item) and make sure that there are no malfunctions.
| B |
|
ADD HV COOLANT |
| C |
|
INSPECT FOR COOLANT LEAK AND ADD COOLANT |
| A |
|
CHECK COOLANT HOSE
Check if the hoses of the cooling system are kinked or clogged.
| NG |
|
CORRECT THE PROBLEM |
| OK |
|
PERFORM ACTIVE TEST USING GTS (CONTROL THE ELECTRIC COOLING FAN)
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Electric Cooling Fan.
Perform the "Control the Electric Cooling Fan" Active Test.
| OK |
|---|
| The cooling fan rotates. |
Turn the power switch off.
| NG |
|
CHECK COOLING FAN SYSTEM Click here |
| OK |
|
PERFORM ACTIVE TEST USING GTS (ACTIVATE THE WATER PUMP)
Note
Be sure to perform the inspection with the auxiliary battery voltage at 11 V or more.
Be sure that the coolant level is above the low line of the inverter reserve tank assembly.
Tech Tips
When the auxiliary battery voltage is low, the inverter water pump assembly may not operate.
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Enter the following menus: Powertrain / Hybrid Control / Active Test / Activate the Water Pump.
Select Inverter W/P Revolution in the Data List.
While performing the "Activate the Water Pump" Active Test, check Inverter W/P Revolution in the Data List.
| Result | ||||||
|---|---|---|---|---|---|---|
|
Tech Tips
Perform the Active Test with the inverter coolant temperature between -15 and 65°C (5 to 149°F).
Turn the power switch off.
| NG |
|
CHECK CONNECTOR CONNECTION CONDITION (POWER MANAGEMENT CONTROL ECU CONNECTOR) Click here |
| OK |
|
READ VALUE USING GTS
Turn the power switch off and leave the vehicle for at least 1 hour.
Connect the GTS 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 | ||||||
|---|---|---|---|---|---|---|
|
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 GTS may be lower than the others, but this is not a malfunction.
Turn the power switch off.
| B |
|
REFER TO REPLACE INVERTER WITH CONVERTER ASSEMBLY PARTS Click here |
| A |
|
CHECK HV COOLANT (CHECK FOR CONDITIONS THAT MAY HAVE CAUSED FREEZING)
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Read the freeze frame data Ambient Temperature using the GTS.
Check if the freeze frame data Ambient Temperature is below freezing.
| Result | ||||||
|---|---|---|---|---|---|---|
|
Tech Tips
HV coolant (SLLC) with a 30% concentration freezes at -15 °C (5°F) and HV coolant (SLLC) with a 50% concentration freezes at -35°C (-31°F).
If the HV coolant freezes in the HV radiator or HV water pump, the coolant temperature in the inverter with converter assembly rises because the HV 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 HV coolant.
If a DTC is set due to freezing of HV coolant, the problem cannot be reproduced. Judge whether freezing of HV coolant occurred according to the freeze point of the HV coolant, HV coolant change history and ambient temperature when the DTC was set.
Turn the power switch off.
| B |
|
REPLACE INVERTER WATER PUMP ASSEMBLY Click here |
| A |
|
REPLACE HV COOLANT
Replace the HV coolant with coolant having an appropriate concentration (appropriate freeze point) for the vehicle usage conditions Click here.
| NEXT |
|
COMPLETED |
CHECK CONNECTOR CONNECTION CONDITION (POWER MANAGEMENT CONTROL ECU CONNECTOR)
Check the connector connections and contact pressure of the relevant terminals for the power management control ECU connectors Click here.
| *A | for LHD | *B | for RHD |
| OK |
|---|
| The connectors are connected securely and there are no contact pressure problems. |
| NG |
|
CONNECT SECURELY |
| OK |
|
CHECK CONNECTOR CONNECTION CONDITION (INVERTER WATER PUMP ASSEMBLY CONNECTOR)
Check the connector connections and contact pressure of the relevant terminals for the inverter water pump assembly connector Click here.
| OK |
|---|
| The connector is connected securely and there are no contact pressure problems. |
| NG |
|
CONNECT SECURELY |
| OK |
|
CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - INVERTER WATER PUMP ASSEMBLY)
Disconnect the A21 power management control ECU connector.
Disconnect the g1 inverter water pump assembly connector.
Measure the resistance according to the value(s) in the table below.
| *a | Rear view of wire harness connector (to Power Management Control ECU) |
*b | Front view of wire harness connector (to Inverter Water Pump Assembly) |
| Standard Resistance (Check for Open) | ||||||
|---|---|---|---|---|---|---|
|
| Standard Resistance (Check for Short) | ||||||
|---|---|---|---|---|---|---|
|
Reconnect the A21 power management control ECU connector.
Reconnect the g1 inverter water pump assembly connector.
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
READ VALUE USING GTS (INVERTER W/P REVOLUTION)
Note
Be sure to perform the inspection with the auxiliary battery voltage at 11 V or more.
Tech Tips
When the auxiliary battery voltage is low, the inverter water pump assembly may not operate.
Connect the GTS to the DLC3.
| *1 | Engine Room Relay Block and Junction Block Assembly |
| *2 | IGCT No. 3 Fuse |
Remove the IGCT No. 3 fuse from the engine room relay block and junction block assembly.
Turn the power switch on (IG).
Enter the following menus: Powertrain / Hybrid Control / ECU Data List / Inverter W/P Revolution.
Read the Data List.
| Result | ||||||
|---|---|---|---|---|---|---|
|
Turn the power switch off.
Install the IGCT No. 3 fuse.
| NG |
|
REPLACE POWER MANAGEMENT CONTROL ECU Click here |
| OK |
|
CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - INVERTER WATER PUMP ASSEMBLY)
Disconnect the A21 power management control ECU connector.
Turn the power switch on (IG).
| *a | Rear view of wire harness connector (to Power Management Control ECU) |
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | ||||||
|---|---|---|---|---|---|---|
|
Note
Turning the power switch on (IG) with the power management control ECU connector disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.
Turn the power switch off.
Reconnect the A21 power management control ECU connector.
| NG |
|
REPLACE INVERTER WATER PUMP ASSEMBLY Click here |
| OK |
|
CHECK POWER MANAGEMENT CONTROL ECU
Turn the power switch on (IG).
| *a | Component with Harness Connected (Power Management Control ECU) |
While turning the power switch on (IG), check the waveform between the power management control ECU terminals.
| Item | Content |
|---|---|
| Terminal | A21-13 (IWP) - L5-6 (E1) |
| Equipment Setting | 5 V/DIV., 50 ms./DIV. |
| Condition | Power switch on (IG) |
| OK |
|---|
| Waveform duty ratio is between 3% and 9%. |
Turn the power switch off.
| OK |
|
REPLACE INVERTER WATER PUMP ASSEMBLY Click here |
| NG |
|
REPLACE POWER MANAGEMENT CONTROL ECU Click here |