P0A78-523
Diagnostic trouble codes
DESCRIPTION
Refer to the description of the inverter. (Click here)| DTC No. |
INF Code |
DTC Detection Condition |
Trouble Area |
| P0A78 |
523 |
Inverter voltage (VH) sensor offset malfunction |
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- HINT:
- Turning the ignition switch off causes the voltage in the inverter to discharge. The inverter voltage is almost 0 V after discharge. The DTC will be stored if the inverter voltage is more than the specified value after discharge.
MONITOR DESCRIPTION
The HV control ECU monitors the inverter voltage (VH) sensor signal. If the HV control ECU detects a fault in the sensor signal, the HV control ECU interprets this as a VH sensor failure. The HV control ECU then illuminates the MIL and sets a DTC.INSPECTION PROCEDURE
- CAUTION:
- Before inspecting the high-voltage system, take safety precautions to prevent electrical shocks, such as wearing insulated gloves and removing the service plug grip. After removing the service plug grip, put it in your pocket to prevent other technicians from reconnecting it while you are working on the high-voltage system.
- After disconnecting the service plug grip, wait for at least 5 minutes before touching any of the high-voltage connectors or terminals.
- Before inspecting the high-voltage system, take safety precautions to prevent electrical shocks, such as wearing insulated gloves and removing the service plug grip. After removing the service plug grip, put it in your pocket to prevent other technicians from reconnecting it while you are working on the high-voltage system.
- HINT:
- At least 5 minutes is required to discharge the high-voltage capacitor inside the w/ converter inverter assembly.
| 1. READ VALUE OF INTELLIGENT TESTER (VL AND VH) |
Connect the intelligent tester to the DLC3.
Turn the ignition switch to the ON position.
Select the following menu items: Powertrain / Hybrid Control / Data List / VL and VH.
- Standard Voltage:
ECU Data List
Specified Condition
Pre-boost voltage (VL)
Below 50 V
Post-boost voltage (VH)
Below 50 V
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| OK | |
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| 2. CHECK FREEZE FRAME DATA INFORMATION (PWR RESOURCE VB, VL AND VH) |
Connect the intelligent tester to the DLC3.
Turn the ignition switch to the ON position.
Select the following menu items: Powertrain / Hybrid Control / DTC / Freeze frame data / Pwr Resource VB, VL and VH.
- OK:
- HV battery voltage (Pwr Resource VB), pre-boost voltage (VL), and post-boost voltage (VH) are almost equal. (The difference among them is within 55 V.)
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| NO | ||
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