Last Modified: 08-21-2023 6.11:8.1.0 Doc ID: RM100000001YKJH
Model Year Start: 2022 Model: Avalon HV Prod Date Range: [08/2021 -           ]
Title: HYBRID / BATTERY CONTROL: MOTOR GENERATOR CONTROL SYSTEM (for LITHIUM-ION BATTERY): P1CCC96; DC/DC Converter Enable Component Internal Failure; 2022 MY Avalon HV [08/2021 -        ]

DTC

P1CCC96

DC/DC Converter Enable Component Internal Failure

DESCRIPTION

The DC/DC converter converts the DC 259 V of the HV battery into DC 12 V in order to supply power to areas such as the vehicle lighting system, audio system and various ECUs. Additionally, it charges the auxiliary battery.

A transistor bridge circuit initially converts DC 259 V into alternating current, and a transformer lowers the voltage.

The DC/DC converter controls the output voltage in order to keep a constant voltage at the terminals of the auxiliary battery.

Then, it is rectified and smoothed (into direct current) and converted into DC 12 V.

The motor generator control ECU sends a signal to the DC/DC converter to prohibit its control and receives signals indicating a normal or abnormal condition of the 12 V charging system via the NODD signal line.

If the DC/DC converter malfunctions, the vehicle will become inoperative. Therefore, the motor generator control ECU monitors the operation of the DC/DC converter and detects malfunctions.

This DTC is stored when the DC/DC converter circuit has a malfunction or its operation is prohibited by a fail-safe function, or the auxiliary battery voltage drops to 11 V or less with the power switch on (READY).

If a DC/DC converter malfunction occurs, DC/DC converter malfunction signals are sent from the DC/DC converter to the MG ECU via the NODD signal line.

This DTC may also be stored if a malfunction of the inverter cooling system (blockage, inverter water pump malfunction, etc.) or a high-voltage insulation malfunction occurs.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Warning Indicate

P1CCC96

DC/DC Converter Enable Component Internal Failure

Both of the following conditions are met:

  • The DC/DC converter is malfunctioning and the auxiliary battery voltage is 11 V or less.*
  • The inverter coolant temperature is 70 °C (158 °F) or lower for 60 seconds.

(1 trip detection logic)

  • Fusible link block assembly
  • Engine wire
  • Inverter cooling system
  • Cooling fan system
  • Grille shutter system
  • Inverter with converter assembly
  • Hybrid vehicle transaxle assembly
  • Motor cable

Does not come on

Master Warning Light:

Comes on

HINT:

*: If the DC/DC converter is malfunctioning, its operation and charging will be stopped and the auxiliary battery voltage will drop.

WIRING DIAGRAM

Refer to the wiring diagram for the Generator High-voltage Circuit.

Click here 2021 - 2022 MY Avalon HV [08/2020 -        ]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY): Generator High-voltage Circuit+

Refer to the wiring diagram for the Motor High-voltage Circuit.

Click here 2021 - 2022 MY Avalon HV [08/2020 -        ]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY): Motor High-voltage Circuit+

CAUTION / NOTICE / HINT

CAUTION:

  • Before the following operations are conducted, take precautions to prevent electric shock by turning the power switch off, wearing insulated gloves, and removing the service plug grip from HV battery.
    • Inspecting the high-voltage system
    • Disconnecting the low voltage connector of the inverter with converter assembly
    • Disconnecting the low voltage connector of the HV battery
  • To prevent electric shock, make sure to remove the service plug grip to cut off the high voltage circuit before servicing the vehicle.
  • After removing the service plug grip from the HV battery, 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 2022 MY Avalon HV [08/2021 -        ]; HYBRID / BATTERY CONTROL: MOTOR GENERATOR CONTROL SYSTEM (for LITHIUM-ION BATTERY): PRECAUTION

    HINT:

    Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

    *a

    Without waiting for 10 minutes

NOTICE:

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 2019 - 2022 MY Avalon Avalon HV [04/2018 -        ]; INTRODUCTION: REPAIR INSTRUCTION: PRECAUTION

HINT:

  • 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.
    1. 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 "BATT Voltage (Hybrid control system)" 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 will gradually drop.)

      1. Headlight switch is in the HI position.
      2. A/C blower fan switch is in the HI position.
      3. Window defogger switch is turned on.
  • By performing the following procedure, the DC/DC converter function can be checked.
    1. Connect the AC/DC 400 A probe to the positive (+) auxiliary battery cable.
      1. Turn the power switch on (READY) and leave the vehicle as is until the electric current flowing to the auxiliary battery becomes 10 A or less.
      2. Turn the power switch on (READY) and turn the headlight switch and A/C blower fan switch to the HI position and the window defogger on.
      3. Confirm that the current drawn from the auxiliary battery is 0 A or lower and the auxiliary battery voltage is between 12.5 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.
  • 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. Also, if this vehicle is jump started by a vehicle with a 24 V battery, 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 in 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

1.

CHECK DTC OUTPUT

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Enter the following menus: Powertrain / Engine, Hybrid Control and Motor Generator / Trouble Codes.

(d) Check for DTCs.

Powertrain > Engine > Trouble Codes

Powertrain > Hybrid Control > Trouble Codes

Powertrain > Motor Generator > Trouble Codes

Result

Proceed to

P1CCC96 only is output, or DTCs except the ones in the table below are also output.

A

DTCs of hybrid control system in the table below are output.

B

DTCs of motor generator control system in the table below are output.

C

DTCs of SFI system in the table below are output.

D

Table 1

Malfunction Content

System

Relevant DTC

Insulation Malfunction

Hybrid control system

P1C7C49

Hybrid/EV Battery Voltage System Isolation (A/C Area) Internal Electronic Failure

P1C7D49

Hybrid/EV Battery Voltage System Isolation (Hybrid/EV Battery Area) Internal Electronic Failure

P1C7E49

Hybrid/EV Battery Voltage System Isolation (Transaxle Area) Internal Electronic Failure

P1C7F49

Hybrid/EV Battery Voltage System Isolation (Direct Current Area) Internal Electronic Failure

High Voltage Circuit Malfunction

Hybrid control system

P0AA649

Hybrid/EV Battery Voltage System Isolation Internal Electronic Failure

P0AD911

Hybrid/EV Battery Positive Contactor Circuit Short to Ground

P0ADD11

Hybrid/EV Battery Negative Contactor Circuit Short to Ground

P0AE411

Hybrid/EV Battery Precharge Contactor Circuit Short to Ground

P1C8449

High Voltage Power Resource Circuit Short during Ready ON

P300449

High Voltage Power Resource Circuit Short during Pre-Charge

Table 2

Malfunction Content

System

Relevant DTC

System malfunction

Hybrid control system

P0A9300

Inverter "A" Cooling System Performance

P0C7396

Motor Electronics Coolant Pump "A" Component Internal Failure

P314A31

Motor Electronics Coolant Pump "A" No Signal

Motor generator control system

P0E5717

DC/DC Converter Voltage Sensor "A" (VL) Circuit Voltage Above Threshold

SFI system

P059A71

Active Grille Air Shutter "A" Actuator Stuck

P059A79

Active Grille Air Shutter "A" Mechanical Linkage Failure

P05A212

Active Grille Air Shutter "A" Circuit Short to Battery

P15AD87

Active Grille Air Shutter "A" Missing Message

HINT:

P1CCC96 may be output as a result of the malfunction indicated by the DTCs above.

  1. The chart above is listed in inspection order of priority.
  2. Check DTCs that are output at the same time by following the listed order. (The main cause of the malfunction can be determined without performing unnecessary inspections.)

(e) Turn the power switch off.

B

GO TO DTC CHART (HYBRID CONTROL SYSTEM)

C

GO TO DTC CHART (MOTOR GENERATOR CONTROL SYSTEM)

D

GO TO DTC CHART (SFI SYSTEM)

A

2.

CHECK AMD TERMINAL CONNECTION CONDITION

CAUTION:

Be sure to wear insulated gloves.

(a) Check that the service plug grip is not installed.

NOTICE:

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.

(b) Check that the nuts for the AMD terminal are tightened to the specified torque, the AMD terminal is connected securely, and there are no contact problems.

Torque:

Inverter with converter assembly side

T=10 N*m (102 kgf*cm, 7 ft.*lbf)

No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly Side

T=8.0 N*m (82 kgf*cm, 71 in.*lbf)

Result:

Result

Proceed to

There are no arc marks.

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

A

There are no arc marks.

The terminal is not connected securely and there is a contact problem.

B

There are arc marks.

-

C

*1

AMD Terminal

(Inverter with Converter Assembly Side)

*2

AMD Terminal

(No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly Side)

B

CONNECT SECURELY

C

REPLACE MALFUNCTIONING PARTS

A

3.

CHECK AMD TERMINAL VOLTAGE

CAUTION:

Be sure to wear insulated gloves.

(a) Connect the cable to the negative (-) auxiliary battery terminal.

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

1G-1 (AMD) - Body ground

Power switch off

Same as auxiliary battery voltage

(c) Disconnect the cable from the negative (-) auxiliary battery terminal.

NG

GO TO STEP 7

OK

4.

CHECK ENGINE WIRE

CAUTION:

Be sure to wear insulated gloves.

(a) Check that the service plug grip is not installed.

NOTICE:

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.

(b) Disconnect the engine wire from the AMD terminal (inverter with converter assembly side and No. 1 engine room relay block side).

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

C64-1 (AMD) - 1G-1 (AMD)

Always

Below 1 Ω

(d) Install the engine wire.

NG

REPLACE ENGINE WIRE

OK

5.

CHECK COOLING SYSTEM

Click here 2022 MY Avalon HV [08/2021 -        ]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY): Cooling System

NEXT

6.

CHECK DC/DC CONVERTER FUNCTION

HINT:

The current at the AMD terminal cannot be measured directly because of space limitations. Measure the current flowing at the auxiliary battery instead.

(a) Connect the AC/DC 400 A probe of the tester to the positive (+) auxiliary battery cable.

(b) Install the service plug grip.

(c) Connect the cable to the negative (-) auxiliary battery terminal.

(d) Turn the power switch on (READY) and leave the vehicle as it is until the electric current flowing to the auxiliary battery becomes 10 A or less.

HINT:

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.

(e) 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.

*a

Probe Direction

*b

Current Flowing to Auxiliary Battery

*a

Probe Direction

*b

Current Flowing from Auxiliary Battery

Standard Current:

Item

Condition

Specified Condition

Current flowing from auxiliary battery

Power switch on (READY)

(The headlight position switch and blower motor switch are in the HI position, and the rear window defogger is turned on.)

0 A or less

(no current from auxiliary battery)

(f) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Item

Condition

Specified Condition

Auxiliary battery voltage

Power switch on (READY)

(The headlight position switch and blower motor switch are in the HI position, and the rear window defogger is turned on.)

12.5 to 15 V

(g) Turn the power switch off.

OK

REPLACE INVERTER WITH CONVERTER ASSEMBLY

NG

GO TO STEP 8

7.

CHECK FUSIBLE LINK (DC/DC)

(a) Disconnect the cable from the negative (-) auxiliary battery terminal.

(b) Remove the fusible link block assembly (DC/DC).

*1

Fusible link block assembly

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

1G-1 - 1F-1

Always

Below 1 Ω

OK

REPAIR OR REPLACE WIRE HARNESS

NG

REPLACE FUSIBLE LINK BLOCK ASSEMBLY (DC/DC)

8.

CHECK HIGH VOLTAGE INSULATION

CAUTION:

Be sure to wear insulated gloves.

(a) Check that the service plug grip is not installed.

NOTICE:

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.

(b) Remove the inverter cover from the inverter with converter assembly.

(c) Using a megohmmeter set to 500 V, measure the insulation resistance according to the value(s) in the table below.

NOTICE:

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:

Tester Connection

Condition

Specified Condition

W2-1 (W) - Body ground and shield ground

Power switch off

1 MΩ or higher

W2-2 (U) - Body ground and shield ground

Power switch off

1 MΩ or higher

W2-3 (V) - Body ground and shield ground

Power switch off

1 MΩ or higher

W2-4 (W) - Body ground and shield ground

Power switch off

1 MΩ or higher

W2-5 (U) - Body ground and shield ground

Power switch off

1 MΩ or higher

W2-6 (V) - Body ground and shield ground

Power switch off

1 MΩ or higher

HINT:

Perform this inspection while the motor cable are connected.

(d) Install the inverter cover to the inverter with converter assembly.

OK

REPLACE HV CONVERTER KIT

NG

9.

CHECK GENERATOR HIGH-VOLTAGE CIRCUIT

Click here 2021 - 2022 MY Avalon HV [08/2020 -        ]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY): Generator High-voltage Circuit

NEXT

10.

CHECK MOTOR HIGH-VOLTAGE CIRCUIT

Click here 2021 - 2022 MY Avalon HV [08/2020 -        ]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for LITHIUM-ION BATTERY): Motor High-voltage Circuit

HINT:

If the "Motor High-voltage Circuit" inspection results are normal, perform the next step.

NEXT

REPLACE INVERTER WITH CONVERTER ASSEMBLY