Info Added 2017-08-02
| DTC Code | DTC Name |
|---|---|
| P0A08-264 | DC / DC Converter Status Circuit |
DESCRIPTION
The DC/DC converter converts the DC 244.8 V of the HV battery into DC 12 V in order to supply power to areas such as the vehicle's lighting, audio, and ECU systems. In addition, it charges the auxiliary battery. A transistor bridge circuit initially converts DC 244.8 V into alternating current, and a transformer lowers its voltage. Then, it is rectified and smoothed (into DC) and converted into DC 12 V. The DC/DC converter controls the output voltage in order to keep a constant voltage at the terminals of the auxiliary battery.
The hybrid vehicle control ECU assembly uses the NODD signal line to transmit a stop command to the DC/DC converter and receive signals indicating the normal or abnormal condition of the 12 V charging system. If the vehicle is being driven with an inoperative DC/DC converter, the voltage of the auxiliary battery will drop, which will prevent the continued operation of the vehicle. Therefore, the hybrid vehicle control ECU assembly monitors the operation of the DC/DC converter and alerts the driver if it detects a malfunction.
This DTC is stored when the DC/DC converter circuit has a malfunction or its operation is prohibited by a fail-safe function, and the auxiliary battery voltage drops to 11 V or less with the power switch on (READY). A signal indicating a DC/DC converter malfunction is sent from the DC/DC converter to the hybrid vehicle control ECU assembly via the NODD signal line.
| DTC No. | INF Code | DTC Detection Condition | Trouble Area |
|---|---|---|---|
| P0A08 | 264 | The DC/DC converter is malfunctioning (charging has stopped) and the auxiliary battery voltage drops to 11 V or less. (1 trip detection logic) The DC/DC converter is malfunctioning for 120 seconds and the inverter coolant water temperature is 70°C or lower. (1 trip detection logic) |
|
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
If there is a malfunction in the DC/DC converter internal circuit, P0A08-264 is stored within 2 minutes of the power switch being turned on (READY) regardless of the auxiliary battery voltage.
If the auxiliary battery voltage is low, the power switch will turn off regardless of DTCs being stored or not.
After repair, clear the DTCs, turn the power switch off and wait for 30 seconds or more and perform the following procedure to confirm that the auxiliary battery low voltage indicated by this DTC has been repaired.
Wait for 2 minutes with the shift lever in P, the power switch on (READY) and the following conditions met, then confirm that Data List item "+B" is between 13.0 and 15.0 V.
(If charging is not performed and the electrical load increases, +B voltage may not be steady and gradually drops.)
Headlight switch is in the HI position.
A/C blower fan switch is in the HI position.
Window defogger switch is turned on.
If the DC/DC converter has an internal malfunction, DTC P0A08-264 is stored regardless of the auxiliary battery voltage after performing this procedure.
If the auxiliary battery voltage drops, the power switch turns off regardless of DTCs being stored or not.
By performing the following procedure, the DC/DC converter function can be checked.
Connect the AC/DC 400 A probe to the positive auxiliary battery cable.
Turn the power switch on (READY) and leave the vehicle as it is until the electric current flowing into the auxiliary battery becomes 10 A or less.
Turn the power switch on (READY) and the headlight switch and A/C blower fan switch in the HI position, and the window defogger turned on.
Confirm that the current drawn from the auxiliary battery is 0 A or lower and the auxiliary battery voltage is between 13.0 and 15.0 V.
This DTC may be also stored when a part other than the DC/DC converter is malfunctioning or depending on user operation.
| Malfunction Case | Remarks | Inspection Step |
|---|---|---|
| High-voltage insulation between the inverter, generator (MG1), motor (MG2) and body ground is poor (body ground). | DTC P0AA6 may be stored if the ground potential fluctuates due to a high-voltage insulation malfunction. | 1 |
| Fuse is blown. (DC/DC-S) | - | 2 |
| A signal connector of the hybrid vehicle control ECU assembly or inverter is not connected securely. | - | 3, 4 |
| A fusible link is blown (DC/DC) | - | 5 |
| High-voltage insulation fault of the following (ground to body).
|
DTC P0A08-264 may be stored if the ground potential fluctuates due to a high-voltage insulation malfunction. | 6, 17, 18, 21 to 24 |
| Check low-voltage line from the inverter to the hybrid vehicle control ECU assembly | Inspect the continuity and connection condition of the AMD and S lines. | 7 to 10 |
| NODD signal line |
|
11, 19 |
| The DC/DC converter is malfunctioning. | Inspect the DC/DC converter function. | 12 |
| Control is suspended due to overheating. (The inverter water pump assembly is malfunctioning, the coolant is not sufficient, a hose is clogged, etc.) | When the inverter is overheating, the DC/DC converter has self protection control that suspends the DC/DC converter control. As that time, this DTC may be stored. The suspended DC/DC converter control will return to normal by clearing the DTCs and turning the power switch off. |
13 to 16, 20 |
| Check areas that caused the blown fuse (DC/DC-S) | - | 25 to 27 |
If this vehicle is used to jump start another vehicle with a discharged battery, a fuse may blow due to overcurrent or the DC/DC converter self-protection may be activated.
In addition, if this vehicle is jump started by a vehicle with a 24 V auxiliary battery or the auxiliary battery cables are connected to the opposite auxiliary battery terminals, the same malfunction may occur and this DTC may be stored. (The suspended DC/DC converter control will return to normal by clearing the DTCs and turning the power switch off.)
Confirm that high electrical load equipment such as a high-capacitance audio device or electric kettle is used on the vehicle. (A fuse of the auxiliary battery may be blown due to overcurrent.)
If the DC/DC converter is malfunctioning, the auxiliary battery cannot be charged. Therefore, once the power switch is turned off, it may be impossible to turn it on (READY) again if the auxiliary battery is completely discharged. In this case, charge the auxiliary battery. Be careful as charging is not performed during the inspection.
If the power switch turns off immediately after it is turned on (READY), the auxiliary battery voltage may be low. Charge the auxiliary battery.
PROCEDURE
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 for DTCs.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| DTC No. | Relevant Diagnosis |
|---|---|
| P0A1B-547 | Drive Motor "A" Control Module |
| P0A40-549 | Drive Motor "A" Position Sensor Circuit Range / Performance |
| P0A78-548 | Drive Motor "A" Inverter Performance |
| P0A93-346 | Inverter Cooling System Performance |
| P0AA6-526, 613 | Hybrid Battery Voltage System Isolation Fault |
| P0ADB-227 | Hybrid Battery Positive Contactor Control Circuit Low |
| P0ADF-229 | Hybrid Battery Negative Contactor Control Circuit Low |
| P0AE6-225 | Hybrid Battery Precharge Contactor Control Circuit Low |
| P0C73-776 | Motor Electronics Coolant Pump "A" Control Performance |
| P3004-131, 803 | High Voltage Power Resource |
| P314A-828 | Inverter Coolant Pump Speed Signal |
Turn the power switch off.
| B |
|
GO TO DTC CHART (HYBRID CONTROL SYSTEM) Click here |
| A |
|
CHECK FUSE (DC/DC-S)
| *1 | Engine Room Relay Block and Junction Block Assembly |
| *2 | DC/DC-S Fuse |
Remove the DC/DC-S fuse from the engine room relay block and junction block assembly.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
Install the DC/DC-S fuse.
| NG |
|
CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - DC/DC-S FUSE) Click here |
| OK |
|
CHECK CONNECTOR CONNECTION CONDITION (HYBRID VEHICLE CONTROL ECU ASSEMBLY CONNECTOR)
| *A | for LHD |
| *B | for RHD |
Check the connector connections and contact pressure of the relevant terminals for the hybrid vehicle control ECU assembly connectors Click here.
| OK |
|---|
| The connectors are connected securely and there are no contact pressure problems. |
| NG |
|
CONNECT SECURELY |
| OK |
|
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.
Check the connector connections and contact pressure of the low voltage connectors of the inverter with converter assembly Click here.
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.
| OK |
|---|
| The connectors are connected securely and there are no contact pressure 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 FUSIBLE LINK BLOCK ASSEMBLY (DC/DC)
Check the fusible link block assembly (DC/DC) in the engine room relay block and junction block assembly for improper installation.
| OK |
|---|
| The fusible link is installed securely. |
Remove the fusible link block assembly from the engine room relay block and junction block assembly.
| *1 | Fusible Link Block Assembly |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
Install the fusible link block assembly.
| NG |
|
REPLACE FUSIBLE LINK BLOCK ASSEMBLY (DC/DC) |
| OK |
|
CHECK CABLE AND WIRE HARNESS
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.
Remove the upper inverter cover (generator cable side) and upper inverter cover (motor cable side) from the inverter with converter assembly.
| *1 | Generator Cable |
| *2 | Motor Cable |
Using a megohmmeter set to 500 V, measure the insulation resistance according to the value(s) in the table below.
Note
Be sure to set the megohmmeter to 500 V when performing this test. Using a setting higher than 500 V can result in damage to the component being inspected.
| Standard Resistance | |||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Tech Tips
Perform this inspection while the generator cable and motor cable are connected.
Install the upper inverter cover (generator cable side) and upper inverter cover (motor cable side).
| NG |
|
CHECK HYBRID VEHICLE TRANSAXLE ASSEMBLY (MG1) Click here |
| OK |
|
CHECK AMD TERMINAL VOLTAGE (ENGINE ROOM RELAY BLOCK AND JUNCTION BLOCK ASSEMBLY SIDE)
CAUTION:
Be sure to wear insulated gloves.
Connect the cable to the negative (-) auxiliary battery terminal.
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | ||||||
|---|---|---|---|---|---|---|
|
Disconnect the cable from the negative (-) auxiliary battery terminal.
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
CHECK AMD TERMINAL CONNECTION CONDITION
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.
Check that the bolt for the AMD terminal (inverter with converter assembly side and engine room relay block and junction block assembly side) is tightened to the specified torque, the AMD terminal (inverter with converter assembly side and engine room relay block and junction block assembly side) is connected securely, and there is no contact problem.
| Torque |
|---|
| T=18 N*m {184 kgf*cm, 13 ft.*lbf } (Inverter with converter assembly side) |
| T=8.0 N*m {82 kgf*cm, 71 in.*lbf } (Engine room relay block and junction block assembly side) |
| Result | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
||||||||||||
| B |
|
CONNECT SECURELY |
| C |
|
REPLACE MALFUNCTIONING PARTS |
| A |
|
CHECK NO. 3 ENGINE ROOM WIRE
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.
Disconnect the No. 3 engine room wire from the AMD terminal (inverter with converter assembly side and engine room relay block and junction block assembly side).
| *1 | No. 3 Engine Room Wire |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
Connect No. 3 engine room wire.
| NG |
|
REPLACE NO. 3 ENGINE ROOM WIRE |
| OK |
|
CHECK HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - DC/DC-S FUSE)
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.
Disconnect the A13 inverter with converter assembly connector.
Connect the cable to the negative (-) auxiliary battery terminal.
| *a | Front view of wire harness connector (to Inverter with Converter Assembly) |
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | ||||||
|---|---|---|---|---|---|---|
|
Disconnect the cable from the negative (-) auxiliary battery terminal.
Reconnect the A13 inverter with converter assembly connector.
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
CHECK HARNESS AND CONNECTOR (RESISTANCE VALUE OF NODD INSIDE HYBRID VEHICLE CONTROL ECU ASSEMBLY)
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.
Disconnect the A13 inverter with converter assembly connector.
| *a | Front view of wire harness connector (to Inverter with Converter Assembly) |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
Reconnect the A13 inverter with converter assembly connector.
| NG |
|
INSPECT HYBRID VEHICLE CONTROL ECU ASSEMBLY (RESISTANCE VALUE OF NODD INSIDE HYBRID VEHICLE CONTROL ECU ASSEMBLY) Click here |
| OK |
|
CHECK DC/DC CONVERTER FUNCTION
Tech Tips
The current at the AMD terminal cannot be measured directly because of space limitations. Measure the current flowing at the auxiliary battery instead.
| *1 | Probe Direction |
| *2 | Current Flowing into Auxiliary Battery |
Connect the AC/DC 400 A probe to the positive auxiliary battery line.
Install the service plug grip.
Connect the cable to the negative (-) auxiliary battery terminal.
Turn the power switch on (READY) and leave the vehicle as it is until the electric current flowing into the auxiliary battery becomes 10 A or less.
Tech Tips
If the power switch turns off immediately after it is turned on (READY), auxiliary battery voltage may be low. Recharge the auxiliary battery and perform this procedure again.
| *1 | Probe Direction |
| *2 | Current Flowing from Auxiliary Battery |
Measure the current flowing from the auxiliary battery with the power switch on (READY), the headlight position switch and blower motor switch in the HI position, and the rear window defogger turned on.
| Standard Current | ||||||
|---|---|---|---|---|---|---|
|
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | ||||||
|---|---|---|---|---|---|---|
|
Turn the power switch off.
| NG |
|
REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here |
| OK |
|
CHECK QUANTITY OF HV COOLANT
Check the HV coolant level in the inverter reserve tank.
Check for HV coolant leaks.
| Result | ||||||||
|---|---|---|---|---|---|---|---|---|
|
Tech Tips
After repairing the HV 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 HV COOLANT LEAK AND ADD HV 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 |
|
CHECK HV COOLANT (CHECK FOR CONDITIONS THAT MAY HAVE CAUSED FREEZING)
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.
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 stored.
A DTC is stored when the water pump impeller cannot rotate due to freezing of the HV coolant.
If a DTC is stored 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 stored.
Turn the power switch off.
| A |
|
REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here |
| B |
|
REPLACE HV COOLANT Click here |
CHECK HYBRID VEHICLE TRANSAXLE ASSEMBLY (MG1)
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.
Remove the upper inverter cover (generator cable side) from the inverter with converter assembly.
| *1 | Generator Cable |
Disconnect the generator cable from the inverter with converter assembly.
| *1 | Shield Ground |
| *a | Generator Cable (Inverter with Converter Assembly Side) |
Using a megohmmeter set to 500 V, measure the insulation resistance according to the value(s) in the table below.
Note
Be sure to set the megohmmeter to 500 V when performing this test. Using a setting higher than 500 V can result in damage to the component being inspected.
| Standard Resistance | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Connect the generator cable.
Install the upper inverter cover.
| NG |
|
REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY Click here |
| OK |
|
CHECK HYBRID VEHICLE TRANSAXLE ASSEMBLY (MG2)
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.
Remove the upper inverter cover (motor cable side) from the inverter with converter assembly.
| *1 | Motor Cable |
Disconnect the motor cable from the inverter with converter assembly.
| *1 | Shield Ground |
| *a | Motor Cable (Inverter with Converter Assembly Side) |
Using a megohmmeter set to 500 V, measure the insulation resistance according to the value(s) in the table below.
Note
Be sure to set the megohmmeter to 500 V when performing this test. Using a setting higher than 500 V can result in damage to the component being inspected.
| Standard Resistance | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Connect the motor cable.
Install the upper inverter cover.
| OK |
|
REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here |
| NG |
|
REPLACE HYBRID VEHICLE TRANSAXLE ASSEMBLY Click here |
INSPECT HYBRID VEHICLE CONTROL ECU ASSEMBLY (RESISTANCE VALUE OF NODD INSIDE HYBRID VEHICLE CONTROL ECU ASSEMBLY)
| *a | Component without harness connected (Hybrid Vehicle Control ECU Assembly) |
Disconnect the A78, A79, H211 and H212 hybrid vehicle control ECU assembly connectors.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
Reconnect the A78, A79, H211 and H212 hybrid vehicle control ECU assembly connectors.
| OK |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| NG |
|
REPLACE HYBRID VEHICLE CONTROL ECU ASSEMBLY Click here |
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 HARNESS AND CONNECTOR (INVERTER WITH CONVERTER ASSEMBLY - DC/DC-S FUSE)
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.
Disconnect the A13 inverter with converter assembly connector.
| *1 | Engine Room Relay Block and Junction Block Assembly |
| *2 | DC/DC-S Fuse |
Remove the DC/DC-S fuse from the engine room relay block and junction block assembly.
Measure the resistance according to the value(s) in the table below.
| *1 | Engine Room Relay Block and Junction Block Assembly | *2 | DC/DC-S Fuse |
| *a | Front view of wire harness connector (to Inverter with Converter Assembly) |
- | - |
| Standard Resistance | ||||||
|---|---|---|---|---|---|---|
|
Install the DC/DC-S fuse.
Reconnect the A13 inverter with converter assembly connector.
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR Click here |
| OK |
|
REPLACE INVERTER WITH CONVERTER ASSEMBLY
| NEXT |
|
REPLACE FUSE (DC/DC-S) |
REPAIR OR REPLACE HARNESS OR CONNECTOR
| NEXT |
|
REPLACE FUSE (DC/DC-S) |