Last Modified: 08-21-2023 6.11:8.1.0 Doc ID: RM100000001A0DY
Model Year Start: 2019 Model: Avalon HV Prod Date Range: [04/2018 - 08/2020]
Title: HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for NICKEL METAL HYDRIDE BATTERY): P1C8149,P1C8249; High Voltage Power Resource Circuit Consumption Circuit Short; 2019 - 2020 MY Avalon HV [04/2018 - 08/2020]

DTC

P1C8149

High Voltage Power Resource Circuit Consumption Circuit Short

DTC

P1C8249

High Voltage Power Resource Circuit Over Loading

DTC SUMMARY

MALFUNCTION DESCRIPTION

The hybrid vehicle control ECU monitors the high-voltage wiring between the HV battery and inverter with converter assembly and detects a short circuit malfunction or high-voltage system operation malfunction.

The cause of this malfunction may be one of the following:

Battery current sensor (IB) circuit malfunction

  • Battery current sensor (IB) malfunction
  • Motor generator control ECU (MG ECU) malfunction
  • Communication (wire harness) malfunction

High voltage system malfunction

  • HV battery malfunction
  • HV battery junction block assembly malfunction
  • Inverter with converter assembly malfunction
  • Air conditioner system malfunction
  • High-voltage wire harness malfunction
  • High-voltage connector or connection malfunction

Low-voltage circuit (12 V) malfunction

  • Hybrid vehicle control ECU malfunction
  • Low voltage wire harness malfunction
  • Low voltage connector malfunction

INSPECTION DESCRIPTION

System Diagram Location

Inspection Content

Reason

Inspection Step

*a

Check high-voltage wiring connection condition of the air conditioner compressor with motor assembly

Check for short circuit

2, 4

*b

Check the high voltage cables between the HV battery junction block assembly and inverter with converter assembly.

Check for short circuit

3, 5

DESCRIPTION

Refer to the description for DTC P0AE411.

Click here 2019 - 2020 MY Avalon HV [04/2018 - 08/2020]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for NICKEL METAL HYDRIDE BATTERY): P0AE411; Hybrid/EV Battery Precharge Contactor Circuit Short to Ground+

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Warning Indicate

P1C8149

High Voltage Power Resource Circuit Consumption Circuit Short

High-voltage circuit malfunctions between the HV battery and inverter with converter assembly.

Excessive overcurrent equal to a short occurs during precharge (time from when SMRP turns on until SMRG turns on).

(1 trip detection logic)
  • Air conditioning wire
  • Compressor with motor assembly
  • Inverter with converter assembly
  • HV battery junction block assembly
  • HV floor under wire

Does not come on

Master Warning Light:

Comes on

P1C8249

High Voltage Power Resource Circuit Over Loading

High-voltage circuit malfunctions between the HV battery and inverter with converter assembly.

Small battery overcurrent occurs during precharge (time from when SMRP turns on until SMRG turns on) and current continues to flow after precharge.

(1 trip detection logic)
  • Air conditioning wire
  • Compressor with motor assembly
  • Inverter with converter assembly
  • HV battery junction block assembly
  • HV floor under wire

Does not come on

Master Warning Light:

Comes on

Related Data List

DTC No.

Data List

P1C8149
  • Hybrid Battery Voltage
  • Hybrid Battery Current
  • VL-Voltage before Boosting
  • VH-Voltage after Boosting

P1C8249

CONFIRMATION DRIVING PATTERN

HINT:

After repair has been completed, clear the DTC and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.

Click here 2019 - 2020 MY Avalon HV [04/2018 - 08/2020]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for NICKEL METAL HYDRIDE BATTERY): UTILITY

  1. Connect the Techstream to the DLC3.
  2. Turn the power switch on (IG) and turn the Techstream on.
  3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
  4. Turn the power switch off and wait for 2 minutes or more.
  5. Turn the power switch on (READY) and wait for 30 seconds or more.
  6. Turn the power switch off and wait for 2 minutes or more.
  7. Turn the power switch on (IG) and turn the Techstream on.
  8. Enter the following menus: Powertrain / Hybrid Control / Utility / All Readiness.
  9. Check the DTC judgment result.

    HINT:

    • If the judgment result shows NORMAL, the system is normal.
    • If the judgment result shows ABNORMAL, the system has a malfunction.
    • If the judgment result shows INCOMPLETE or N/A, perform driving pattern again.

WIRING DIAGRAM

Refer to the wiring diagram for DTC P0AA649.

Click here 2019 - 2020 MY Avalon HV [04/2018 - 08/2020]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for NICKEL METAL HYDRIDE BATTERY): P0AA649,...,P1C7F49; Hybrid/EV Battery Voltage System Isolation Internal Electronic Failure+

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 2019 - 2020 MY Avalon HV [04/2018 - 08/2020]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for NICKEL METAL HYDRIDE 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
  • If this DTC is output, do not turn the power switch on (READY) until the repair has been completed. This DTC means an excessive amperage flow through the system main resistor. The system main resistor may overheat and be damaged if the power switch is turned on (READY) repeatedly before repair.

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

PROCEDURE

1.

CHECK DTC OUTPUT (HYBRID CONTROL, MOTOR GENERATOR)

(a) Connect the Techstream to the DLC3.

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

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

(d) Check for DTCs.

Powertrain > Hybrid Control > Trouble Codes

Powertrain > Motor Generator > Trouble Codes

Result

Proceed to

P1C8149 or P1C8249 only is output, or DTCs except the ones in the tables below are also output.

A

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

B

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

C

Malfunction Content

System

Relevant DTC

Microcomputer malfunction

Hybrid control system

P060647

Hybrid/EV Powertrain Control Module Processor Watchdog / Safety MCU Failure

P0AFC96

Hybrid/EV Battery Sensor Module Component Internal Failure

P0AFC00

Hybrid/EV Battery Sensor Module

Power source circuit malfunction

Hybrid control system

P0AFC16

Hybrid/EV Battery Sensor Module Circuit Voltage Below Threshold

Communication system malfunction

Hybrid control system

U029A87

Lost Communication with Hybrid/EV Battery Sensor Module Missing Message

Sensor and actuator circuit malfunction

Hybrid control system

P0ABF11

Hybrid/EV Battery Current Sensor "A" Circuit Short to Ground

P0ABF15

Hybrid/EV Battery Current Sensor "A" Circuit Short to Auxiliary Battery or Open

P0B3B14

Hybrid/EV Battery Voltage Sensor "A" Circuit Short to Ground or Open

P0B4014

Hybrid/EV Battery Voltage Sensor "B" Circuit Short to Ground or Open

P0B4514

Hybrid/EV Battery Voltage Sensor "C" Circuit Short to Ground or Open

P0B4A14

Hybrid/EV Battery Voltage Sensor "D" Circuit Short to Ground or Open

P0B4F14

Hybrid/EV Battery Voltage Sensor "E" Circuit Short to Ground or Open

P0B5414

Hybrid/EV Battery Voltage Sensor "F" Circuit Short to Ground or Open

P0B5914

Hybrid/EV Battery Voltage Sensor "G" Circuit Short to Ground or Open

P0B5E14

Hybrid/EV Battery Voltage Sensor "H" Circuit Short to Ground or Open

P0B6314

Hybrid/EV Battery Voltage Sensor "I" Circuit Short to Ground or Open

P0B6814

Hybrid/EV Battery Voltage Sensor "J" Circuit Short to Ground or Open

P0B6D14

Hybrid/EV Battery Voltage Sensor "K" Circuit Short to Ground or Open

P0B7214

Hybrid/EV Battery Voltage Sensor "L" Circuit Short to Ground or Open

P308A13

Hybrid/EV Battery Voltage Sensor All Circuit Open

P0AFC62

Hybrid/EV Battery Sensor Module Signal Compare Failure

P0B231C

Hybrid/EV Battery "A" Voltage Sensor Voltage Out of Range

P308A12

Hybrid/EV Battery Voltage Sensor All Circuit Short to Auxiliary Battery

P0ABF00

Hybrid/EV Battery Current Sensor "A" Circuit Range/Performance

P0ABF28

Hybrid/EV Battery Current Sensor "A" Signal Bias Level Out of Range / Zero Adjustment Failure

P0ABF2A

Hybrid/EV Battery Current Sensor "A" Signal Stuck In Range

Motor generator control system

P0A1114

DC/DC Converter Enable Circuit Short to Ground or Open

P0A1112

DC/DC Converter Enable Circuit Short to Battery

P1CCC96

DC/DC Converter Enable Component Internal Failure

System malfunction

Motor generator control system

P0D3319

DC/DC Converter Circuit Current Above Threshold

HINT:

  • P1C8149 or P1C8249 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)

A

2.

CHECK COMPRESSOR WITH MOTOR ASSEMBLY

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 air conditioning wire connector from the inverter with converter assembly.

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

Standard Resistance:

Tester Connection

(Tester Probe Polarity)

Condition

Specified Condition

T2-2 (ACPE) (Negative (-) probe) - T2-1 (ACPB) (Positive (+) probe)

Power switch off

100 kΩ or higher

NOTICE:

  • Do not use a megohmmeter.
  • Read the resistance after the value has stabilized.
  • Be sure to inspect with connecting the tester probes to the tips of the terminal.

*a

Air conditioning wire

(Inverter with Converter Assembly Side)

*b

Tip of Terminal

(d) Reconnect the air conditioning wire connector.

NG

GO TO STEP 4

OK

3.

CHECK HV FLOOR UNDER 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 HV floor under wire connector from the inverter with converter assembly.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

S1-1 (CBI) - S1-2 (CEI)

Power switch off

10 kΩ or higher

NOTICE:

Be sure not to damage or deform the terminal being inspected.

*a

HV Floor Under Wire

(Inverter with Converter Assembly Side)

(d) Reconnect the HV floor under wire connector.

OK

REPLACE INVERTER WITH CONVERTER ASSEMBLY

NG

GO TO STEP 5

4.

CHECK HV AIR CONDITIONING 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 HV air conditioning wire connector from the inverter with converter assembly.

(c) Disconnect the HV air conditioning wire from the compressor with motor assembly.

Click here 2019 - 2021 MY Avalon HV [04/2018 - 08/2021]; HEATING / AIR CONDITIONING: COMPRESSOR (for A25A-FXS): REMOVAL+

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

T2-2 (ACPE) - T2-1 (ACPB)

Power switch off

10 kΩ or higher

NOTICE:

Be sure to inspect with connecting the tester probes to the tips of the terminal.

*a

HV air conditioning wire

(Inverter with Converter Assembly Side)

*b

Tip of Terminal

(e) Reconnect the HV air conditioning wire connector to the inverter with converter assembly.

(f) Reconnect the HV air conditioning wire to the compressor with motor assembly.

OK

REPLACE COMPRESSOR WITH MOTOR ASSEMBLY

NG

REPLACE HV AIR CONDITIONING WIRE

5.

CHECK HV FLOOR UNDER 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) Remove the No. 1 HV battery cover panel RH.

Click here 2019 - 2020 MY Avalon HV [04/2018 - 08/2020]; HYBRID / BATTERY CONTROL: HV BATTERY (for NICKEL METAL HYDRIDE BATTERY): REMOVAL+

(c) Disconnect the HV floor under wire connectors from the HV battery junction block assembly.

(d) Disconnect the HV floor under wire connector from the inverter with converter assembly.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

S1-1 (CBI) - S1-2 (CEI)

Power switch off

10 kΩ or higher

NOTICE:

Be sure not to damage or deform the terminal being inspected.

*a

HV Floor Under Wire

(Inverter with Converter Assembly Side)

(f) Reconnect the HV floor under wire connector to the inverter with converter assembly.

(g) Reconnect the HV floor under wire connectors to the HV battery junction block assembly.

(h) Install the No. 1 HV battery cover panel RH.

OK

REPLACE HV BATTERY JUNCTION BLOCK ASSEMBLY

NG

REPLACE HV FLOOR UNDER WIRE