- Hybrid/EV Battery Voltage
- Hybrid/EV Battery Current
- VL-Voltage before Boosting
- VH-Voltage after Boosting
| Last Modified: 05-13-2024 | 6.11:8.1.0 | Doc ID: RM100000001O4KH |
| Model Year Start: 2021 | Model: Corolla | Prod Date Range: [04/2020 - 09/2022] |
| Title: HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for NICKEL METAL HYDRIDE BATTERY): P1C8449; High Voltage Power Resource Circuit Short during Ready ON; 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022] | ||
|
DTC |
P1C8449 |
High Voltage Power Resource Circuit Short during Ready ON |
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 an open circuit malfunction.
HINT:
- This DTC is differentiated from P300449 based on detection timing (after power switch is turned on (READY)). If P300449 is also output at the same time, first perform troubleshooting for P300449.
- If there is a SMRG stuck open malfunction, only P1C8449 is output.
The cause of this malfunction may be one of the following:
Inverter voltage sensor (VH or VL) internal circuit malfunction
- Voltage sensor (VH or VL) 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
- High-voltage wire harness malfunction
- High-voltage connector or connection malfunction
Low-voltage circuit (12 V) malfunction
- Hybrid vehicle control ECU malfunction
- HV battery junction block assembly malfunction
- Low voltage wire harness malfunction
- Low voltage connector malfunction
DESCRIPTION
Refer to the description for DTC P0AE411.
Click here
![2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022]; HYBRID / BATTERY CONTROL: HYBRID CONTROL SYSTEM (for NICKEL METAL HYDRIDE BATTERY): P0AE411; Hybrid/EV Battery Precharge Contactor Circuit Short to Ground+](/t3Portal/stylegraphics/info.gif)
|
DTC No. |
Detection Item |
DTC Detection Condition |
Trouble Area |
MIL |
Warning Indicate |
|---|---|---|---|---|---|
|
P1C8449 |
High Voltage Power Resource Circuit Short during Ready ON |
High-voltage circuit malfunctions between the HV battery and inverter with converter assembly. The voltage before boosting continues to be out of the HV battery voltage range or the integrated value of variation amount of the voltage before boosting for a specified period of time is large while the power switch is on (READY). The EV electric battery fuse is blown, the service plug grip is removed, SMRB or SMRG remains open, or the high-voltage cable has an open circuit. (1 trip detection logic) |
|
Comes on |
Master Warning: Comes on |
Related Data List
|
DTC No. |
Data List |
|---|---|
|
P1C8449 |
|
The following items can be helpful when performing repairs:
Data List
- Ready Signal
MONITOR DESCRIPTION
A malfunction is detected and the MIL is illuminated when the following condition is met:
A large fluctuation of DC/DC converter voltage is occurred due to power cable disconnection.
MONITOR STRATEGY
|
Related DTCs |
P3004 (INF P1C8449): Power Cable Malfunction |
|
Required sensors/components |
DC/DC converter, HV battery |
|
Frequency of operation |
- |
|
Duration |
TMC's intellectual property |
|
MIL operation |
1 driving cycle |
|
Sequence of operation |
None |
TYPICAL ENABLING CONDITIONS
|
The monitor will run whenever the following DTCs are not stored |
TMC's intellectual property |
|
Other conditions belong to TMC's intellectual property |
- |
TYPICAL MALFUNCTION THRESHOLDS
|
TMC's intellectual property |
- |
COMPONENT OPERATING RANGE
|
Hybrid vehicle control ECU |
P3004 (INF P1C8449) is not detected |
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
-
When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.
Click here
- Connect the Techstream to the DLC3.
- Turn the power switch on (IG) and turn the Techstream on.
- Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
- Turn the power switch off and wait for 2 minutes or more.
- Turn the power switch on (IG) and turn the Techstream on.
-
Turn the power switch on (READY) and wait for 3 minutes or more. [*1]
HINT:
- According to the display on the Techstream, read the Data List and monitor the values of "Hybrid/EV Battery Voltage" and "VL-Voltage before Boosting" for 3 minutes. If the difference between "Hybrid/EV Battery Voltage" and "VL-Voltage before Boosting" is always less than 50 V, the vehicle has returned to normal.
-
[*1] : Normal judgment procedure.
The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.
- Enter the following menus: Powertrain / Hybrid Control / Utility / All Readiness.
-
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 the normal judgment procedure again.
WIRING DIAGRAM
Refer to the wiring diagram for the HV Battery High-voltage Line Circuit.
Click here
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
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
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 |
|---|---|
|
P1C8449 only is output, or P0A9563 and DTCs except the ones in the table 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 |
|
P0A9563 is also output. |
D |
|
Malfunction Content |
System |
Relevant DTC |
|
|---|---|---|---|
|
Microcomputer malfunction |
Hybrid control system |
P0A1B49 |
Drive Motor "A" Control Module Internal Electronic Failure |
|
P060647 |
Hybrid/EV Powertrain Control Module Processor Watchdog / Safety MCU Failure |
||
|
P0AFC00 |
Hybrid/EV Battery Sensor Module |
||
|
Motor generator control system |
P0A1B1F |
Generator Control Module Circuit Intermittent |
|
|
P0A1A47 |
Generator Control Module Watchdog / Safety μC Failure |
||
|
P0A1A49 |
Generator Control Module Internal Electronic Failure |
||
|
P1C2A1C |
Generator A/D Converter Circuit Circuit Voltage Out of Range |
||
|
P1C2A49 |
Generator A/D Converter Circuit Internal Electronic Failure |
||
|
P313383 |
Communication Error from Generator to Drive Motor "A" Value of Signal Protection Calculation Incorrect |
||
|
P313386 |
Communication Error from Generator to Drive Motor "A" Signal Invalid |
||
|
Power source circuit malfunction |
Hybrid control system |
P0AFC16 |
Hybrid/EV Battery Sensor Module Circuit Voltage Below Threshold |
|
Motor generator control system |
P06D61C |
Generator Control Module Offset Power Circuit Voltage Out of Range |
|
|
Communication system malfunction |
Hybrid control system |
P312387 |
Lost Communication with Drive Motor Control Module "A" from Hybrid/EV Control Module Missing Message |
|
U029A87 |
Lost Communication with Hybrid/EV Battery Sensor Module Missing Message |
||
|
Motor generator control system |
P313387 |
Communication Error from Generator to Drive Motor "A" Missing Message |
|
|
Sensor and actuator circuit malfunction |
Hybrid control system |
P0ABF00 |
Hybrid/EV Battery Current Sensor "A" Circuit Range/Performance |
|
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 |
||
|
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 |
||
|
P0AD911 |
Hybrid/EV Battery Positive Contactor Circuit Short to Ground |
||
|
P0AD915 |
Hybrid/EV Battery Positive Contactor Circuit Short to Auxiliary Battery or Open |
||
|
P0ADD11 |
Hybrid/EV Battery Negative Contactor Circuit Short to Ground |
||
|
P0ADD15 |
Hybrid/EV Battery Negative Contactor Circuit Short to Auxiliary Battery or Open |
||
|
Motor generator control system |
P0D2D16 |
Drive Motor "A" Inverter Voltage Sensor (VH) Circuit Voltage Below Threshold |
|
|
P0D2D17 |
Drive Motor "A" Inverter Voltage Sensor (VH) Circuit Voltage Above Threshold |
||
|
System malfunction |
Hybrid control system |
P0D2D1C |
Drive Motor "A" Inverter Voltage Sensor Voltage Out of Range |
|
P0E311C |
Boosting Converter Voltage Sensor "A" Voltage Out of Range |
||
|
P1C8349 |
High Voltage Power Resource Circuit Voltage Sensor after Boosting Malfunction |
||
|
P1C2D62 |
Hybrid/EV Battery "A" Voltage Sensor/Boosting Converter Voltage Sensor "A" Signal Compare Failure |
||
|
P300016 |
Hybrid/EV Battery Control System Circuit Voltage Below Threshold |
||
|
P300449 |
High Voltage Power Resource Circuit Short during Pre-Charge |
||
|
Motor generator control system |
P1CB69E |
Drive Motor "A" Inverter Voltage Sensor(VH) Stuck On |
|
|
P0CA300 |
DC/DC Converter Step Up Voltage Performance |
||
HINT:
-
P1C8449 may be output as a result of the malfunction indicated by the DTCs above.
- The chart above is listed in inspection order of priority.
- 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 |
|
| C |
|
| D |
|
|
|
2. |
CLEAR DTC |
Click here
|
|
3. |
CHECK DTC OUTPUT (HYBRID CONTROL) |
(a) Connect the Techstream to the DLC3.
(b) With the vehicle stopped, apply the parking brake and turn the power switch on (READY).
NOTICE:
Perform this test with the AUTO function (shift-linked function) of the electronic parking brake system off.
HINT:
- If the power switch could not be turned on (READY), turn the power switch off and check for DTCs after turning the power switch on (READY) again.
- When the parking brake indicator (red) is illuminated after the electric parking brake switch (electric parking brake switch assembly) has been pulled to the lock side, the maximum amount of braking force is applied if the electric parking brake switch (electric parking brake switch assembly) is pulled to the lock side one more time.
- Because P300449 uses 2 trip detection logic, the DTC detection conditions need to be met 2 times.
(c) Ensure the safety of the areas in front and at the back of the vehicle.
(d) Move the shift lever to D and depress both the accelerator pedal and brake pedal at the same time.
HINT:
Depressing both the accelerator pedal and brake pedal at the same time causes the HV battery current to flow and ensures that there is no problem with the high-voltage wiring.
(e) Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.
(f) Check for DTCs.
Powertrain > Hybrid Control > Trouble Codes
|
Result |
Proceed to |
|---|---|
|
P1C8449 is output, or no DTCs are output. |
A |
|
Power switch could not be turned on (READY) and DTC P300449 is output. |
B |
(g) Turn the power switch off.
| B |
|
|
|
4. |
CHECK CONNECTOR CONNECTION CONDITION (HYBRID VEHICLE CONTROL ECU CONNECTOR) |
Click here
| NG |
|
CONNECT SECURELY |
|
|
5. |
CHECK CONNECTOR CONNECTION CONDITION (FLOOR WIRE CONNECTOR) |
Click here
|
Result |
Proceed to |
|---|---|
|
OK |
A |
|
NG (The connector is not connected securely.) |
B |
|
NG (The terminals are not making secure contact or are deformed, or water or foreign matter exists in the connector.) |
C |
| B |
|
CONNECT SECURELY |
| C |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
6. |
CHECK CONNECTOR CONNECTION CONDITION (HV BATTERY JUNCTION BLOCK ASSEMBLY CONNECTOR) |
Click here
| NG |
|
CONNECT SECURELY |
|
|
7. |
CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - HV BATTERY JUNCTION BLOCK 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) Remove the No. 1 HV battery cover panel RH.
Click here
(c) Disconnect the O35 HV battery junction block assembly connector.
(d) Disconnect the I2 hybrid vehicle control ECU connector.
|
(e) Measure the resistance according to the value(s) in the table below. Standard Resistance:
|
|
(f) Reconnect the I2 hybrid vehicle control ECU connector.
(g) Reconnect the O35 HV battery junction block assembly connector.
(h) Install the No. 1 HV battery cover panel RH.
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
8. |
CHECK HARNESS AND CONNECTOR (HV BATTERY JUNCTION BLOCK ASSEMBLY - BODY GROUND) |
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
(c) Disconnect the O35 HV battery junction block assembly connector.
|
(d) Measure the resistance according to the value(s) in the table below. Standard Resistance:
|
|
(e) Reconnect the O35 HV battery junction block assembly connector.
(f) Install the No. 1 HV battery cover panel RH.
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
9. |
REPLACE HV BATTERY JUNCTION BLOCK ASSEMBLY |
Click here
|
|
10. |
CHECK HYBRID VEHICLE CONTROL ECU (CHECK FOR NORMAL OPERATION) |
CAUTION:
Be sure to wear insulated gloves.
(a) Install the service plug grip.
(b) Turn the power switch on (IG).
(c) Clear the DTCs.
Powertrain > Hybrid Control > Clear DTCs
(d) Turn the power switch off and wait for 2 minutes or more.
(e) Turn the power switch on (READY).
(f) Enter the following menus: Powertrain / Hybrid Control / Data List / VL-Voltage before Boosting, Hybrid/EV Battery Voltage.
Powertrain > Hybrid Control > Data List
|
Tester Display |
|---|
|
VL-Voltage before Boosting |
|
Hybrid/EV Battery Voltage |
(g) According to the display on the Techstream, read the Data List and monitor the values of "Hybrid/EV Battery Voltage" and "VL-Voltage before Boosting" for 3 minutes.
|
Result |
Proceed to |
|---|---|
|
Difference between "Hybrid/EV Battery Voltage" and "VL-Voltage before Boosting" is always less than 50 V. |
A |
|
Difference between "Hybrid/EV Battery Voltage" and "VL-Voltage before Boosting" is 50 V or more. |
B |
(h) Turn the power switch off.
| A |
|
END |
| B |
|
|
|