DTC P0A94-554 DC / DC Converter Performance |
DTC P0A94-555 DC / DC Converter Performance |
| DTC No. | INF Code | DTC Detection Condition | Trouble Area |
| P0A94 | 554 | Boost converter inverter fail signal detection (overcurrent by MG ECU malfunction) |
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| P0A94 | 555 | Boost converter inverter fail signal detection (overcurrent by inverter assembly malfunction) |
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| 1.READ OUTPUT DTC (HV) |
Connect the intelligent tester to the DLC3.
Turn the ignition switch to the ON position.
Select the following menu items: Powertrain / Hybrid Control / DTC.
Read output DTC. (Click here)
| DTC No. | Relevant Diagnosis |
| P0A1D | HV ECU circuit malfunction |
| P0A2B, P0A2C, P0A2D | Motor temperature sensor circuit |
| P0A37, P0A38, P0A39 | Generator temperature sensor circuit |
| P0A3F, P0A40, P0A41 | Motor resolver circuit |
| P0A4B, P0A4C, P0A4D | Generator resolver circuit |
| P0A60, P0A63 | Motor current sensor circuit |
| P0A72, P0A75 | Generator current sensor circuit |
| P0A78 | Motor inverter function malfunction |
| P0A7A | Generator inverter function malfunction |
| P0A90 | Motor function malfunction |
| P0A92 | Generator function malfunction |
| P0A94 (Except for 554 and 555) | Boost converter circuit |
| P0AA1, P0AA2, P0AA4, P0AA5 | System main relay circuit |
| P0AA6, P3004 | High-voltage system |
| P0A79 | Rear motor inverter function malfunction |
| P0A45, P0A46, P0A47 | Rear motor resolver malfunction |
| P0A69, P0A6C, P0A55 | Rear motor current sensor circuit |
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| NO | |
| 2.CHECK CONNECTION CONDITION OF MG ECU CONNECTOR (LOOSENESS AND POOR CONTACT) |
Turn the ignition switch off and remove the service plug grip. (Click here)
Remove the inverter cover. (Click here)
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Check the connections of the MG ECU connectors.
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| OK | |
| 3.INSPECT HYBRID VEHICLE TRANSAXLE ASSEMBLY (MOTOR) |
Check that the service plug grip is removed.
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Disconnect the three-phase AC cable for Motor from the w/ converter inverter assembly.
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Using a milliohmmeter, measure the resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| U - V | 48 to 59 mΩ (20°C) |
| V - W | 48 to 59 mΩ (20°C) |
| W - U | 48 to 59 mΩ (20°C) |
To correct the resistance varying depending on the temperature, use the following formula to calculate the resistance at 20°C.
Calculate the difference between the maximum and minimum resistance.
Using a megohmmeter, measure the insulation resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| U - Body ground and shielded wire ground | 10 MΩ or higher |
| V - Body ground and shielded wire ground | 10 MΩ or higher |
| W - Body ground and shielded wire ground | 10 MΩ or higher |
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| OK | |
| 4.INSPECT HYBRID VEHICLE TRANSAXLE ASSEMBLY (GENERATOR) |
Check that the service plug grip is removed.
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Disconnect the three-phase AC cable for Generator from the w/ converter inverter assembly.
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Using a milliohmmeter, measure the resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| U - V | 109 mΩ or less (20°C) |
| V - W | 109 mΩ or less (20°C) |
| W - U | 109 mΩ or less (20°C) |
To correct the resistance varying depending on the temperature, use the following formula to calculate the resistance at 20°C.
Calculate the difference between the maximum and minimum resistance.
Using a megohmmeter, measure the insulation resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| U - Body ground and shielded wire ground | 10 MΩ or higher |
| V - Body ground and shielded wire ground | 10 MΩ or higher |
| W - Body ground and shielded wire ground | 10 MΩ or higher |
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| OK | |
| 5.INSPECT REAR TRACTION MOTOR W/TRANSAXLE ASSEMBLY |
Check that the service plug grip is removed.
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Disconnect the three-phase AC cable for Rear Motor from the w/ converter inverter assembly.
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Using a milliohmmeter, measure the resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| U - V | 109 mΩ or less (20°C) |
| V - W | 109 mΩ or less (20°C) |
| W - U | 109 mΩ or less (20°C) |
To correct the resistance varying depending on the temperature, use the following formula to calculate the resistance at 20°C.
Calculate the difference between the maximum and minimum resistance.
Using a megohmmeter, measure the insulation resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| U - Body ground and shielded wire ground | 10 MΩ or higher |
| V - Body ground and shielded wire ground | 10 MΩ or higher |
| W - Body ground and shielded wire ground | 10 MΩ or higher |
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| OK | |
| 6.CHECK HARNESS AND CONNECTOR (MG ECU - MOTOR RESOLVER) |
Check that the service plug grip is removed.
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Disconnect the I24 connector from the MG ECU.
Measure the voltage according to the value(s) in the table below when the ignition switch is in the ON position.
| Tester Connection | Specified Condition |
| MRF (I24-13) - Body ground | Below 1 V |
| MRFG (I24-23) - Body ground | Below 1 V |
| MSN (I24-21) - Body ground | Below 1 V |
| MSNG (I24-20) - Body ground | Below 1 V |
| MCS (I24-19) - Body ground | Below 1 V |
| MCSG (I24-18) - Body ground | Below 1 V |
Turn the ignition switch off.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| MRF (I24-13) - MRFG (I24-23) | 7.65 to 10.2 Ω |
| MSN (I24-21) - MSNG (I24-20) | 12.6 to 16.8 Ω |
| MCS (I24-19) - MCSG (I24-18) | 12.6 to 16.8 Ω |
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| MRF (I24-13) or MRFG (I24-23) - Body ground | 10 kΩ or higher |
| MSN (I24-21) or MSNG (I24-20) - Body ground | 10 kΩ or higher |
| MCS (I24-19) or MCSG (I24-18) - Body ground | 10 kΩ or higher |
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| OK | |
| 7.CHECK HARNESS AND CONNECTOR (MG ECU - GENERATOR RESOLVER) |
Check that the service plug grip is removed.
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Disconnect the I24 connector from the MG ECU.
Measure the voltage according to the value(s) in the table below when the ignition switch is in the ON position.
| Tester Connection | Specified Condition |
| GRF (I24-12) - Body ground | Below 1 V |
| GRFG (I24-22) - Body ground | Below 1 V |
| GSN (I24-11) - Body ground | Below 1 V |
| GSNG (I24-10) - Body ground | Below 1 V |
| GCS (I24-9) - Body ground | Below 1 V |
| GCSG (I24-8) - Body ground | Below 1 V |
Turn the ignition switch off.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| GRF (I24-12) - GRFG (I24-22) | 7.65 to 10.2 Ω |
| GSN (I24-11) - GSNG (I24-10) | 12.6 to 16.8 Ω |
| GCS (I24-9) - GCSG (I24-8) | 12.6 to 16.8 Ω |
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| GRF (I24-12) or GRFG (I24-22) - Body ground | 10 kΩ or higher |
| GSN (I24-11) or GSNG (I24-10) - Body ground | 10 kΩ or higher |
| GCS (I24-9) or GCSG (I24-8) - Body ground | 10 kΩ or higher |
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| OK | |
| 8.CHECK HARNESS AND CONNECTOR (MG ECU - REAR MOTOR RESOLVER) |
Check that the service plug grip is removed.
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Disconnect the I25 connector from the MG ECU.
Measure the voltage according to the value(s) in the table below when the ignition switch is in the ON position.
| Tester Connection | Specified Condition |
| RRF (I25-21) - Body ground | Below 1 V |
| RRFG (I25-22) - Body ground | Below 1 V |
| RSN (I25-29) - Body ground | Below 1 V |
| RSNG (I25-30) - Body ground | Below 1 V |
| RCS (I25-11) - Body ground | Below 1 V |
| RCSG (I25-23) - Body ground | Below 1 V |
Turn the ignition switch off.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| RRF (I25-21) - RRFG (I25-22) | 7.65 to 10.2 Ω |
| RSN (I25-29) - RSNG (I25-30) | 12.6 to 16.8 Ω |
| RCS (I25-11) - RCSG (I25-23) | 12.6 to 16.8 Ω |
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| RRF (I25-21) or RRFG (I25-22) - Body ground | 10 kΩ or higher |
| RSN (I25-29) or RSNG (I25-30) - Body ground | 10 kΩ or higher |
| RCS (I25-11) or RCSG (I25-23) - Body ground | 10 kΩ or higher |
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| OK | ||
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| 9.INSPECT MOTOR RESOLVER |
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Disconnect the M7 motor resolver connector.
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Measure the resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| MRF (M7-1) - MRFG (M7-4) | 7.65 to 10.2 Ω |
| MSN (M7-2) - MSNG (M7-5) | 12.6 to 16.8 Ω |
| MCS (M7-3) - MCSG (M7-6) | 12.6 to 16.8 Ω |
Using a megohmmeter, measure the insulation resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| MRF (M7-1) - MSN (M7-2) | 10 MΩor higher |
| MRF (M7-1) - MCS (M7-3) | 10 MΩor higher |
| MSN (M7-2) - MCS (M7-3) | 10 MΩor higher |
| MRFG (M7-4) - MSNG (M7-5) | 10 MΩor higher |
| MRFG (M7-4) - MCSG(M7-6) | 10 MΩor higher |
| MSNG (M7-5) - MCSG (M7-6) | 10 MΩor higher |
| Each terminal listed above - Transaxle housing | 10 MΩor higher |
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| OK | ||
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| 10.INSPECT GENERATOR RESOLVER |
Remove the w/ converter inverter assembly.
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Disconnect the M6 generator resolver connector.
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Measure the resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| GRF (M6-1) - GRFG (M6-6) | 7.65 to 10.2 Ω |
| GSN (M6-2) - GSNG (M6-7) | 12.6 to 16.8 Ω |
| GCS (M6-3) - GCSG (M6-8) | 12.6 to 16.8 Ω |
Using a megohmmeter, measure the insulation resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| GRF (M6-1) - GSN (M6-2) | 10 MΩ or higher |
| GRF (M6-1) - GCS (M6-3) | 10 MΩ or higher |
| GSN (M6-2) - GCS (M6-3) | 10 MΩ or higher |
| GRFG (M6-6) - GSNG (M6-7) | 10 MΩ or higher |
| GRFG (M6-6) - GCSG (M6-8) | 10 MΩ or higher |
| GSNG (M6-7) - GCSG (M6-8) | 10 MΩ or higher |
| Each terminal listed above - Transaxle housing | 10 MΩ or higher |
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| OK | ||
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| 11.INSPECT REAR MOTOR RESOLVER |
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Disconnect the M11 rear motor resolver connector.
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Measure the resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| RRF (M11-1) - RRFG (M11-4) | 7.65 to 10.2 Ω |
| RSN (M11-2) - RSNG (M11-5) | 12.6 to 16.8 Ω |
| RCS (M11-3) - RCSG (M11-6) | 12.6 to 16.8 Ω |
Using a megohmmeter, measure the insulation resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| RRF (M11-1) - RSN (M11-2) | 10 MΩ or higher |
| RRF (M11-1) - RCS (M11-3) | 10 MΩ or higher |
| RSN (M11-2) - RCS (M11-3) | 10 MΩ or higher |
| RRFG (M11-4) - RSNG (M11-5) | 10 MΩ or higher |
| RRFG (M11-4) - RCSG (M11-6) | 10 MΩ or higher |
| RSNG (M11-5) - RCSG (M11-6) | 10 MΩ or higher |
| Each terminal listed above - Transaxle housing | 10 MΩ or higher |
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| OK | ||
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| 12.INSPECT FRAME WIRE NO.3 |
Check that the service plug grip is removed.
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Disconnect the frame wire No.3 from the rear traction motor w/ transaxle assembly.
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Using a megohmmeter, measure the insulation resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| U - Body ground and shielded wire ground | 10 MΩ or higher |
| V - Body ground and shielded wire ground | 10 MΩ or higher |
| W - Body ground and shielded wire ground | 10 MΩ or higher |
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| U - V | 10 kΩ or higher |
| U - W | 10 kΩ or higher |
| V - W | 10 kΩ or higher |
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| OK | |
| 13.INSPECT EXTENSION WIRE ASSEMBLY |
Remove the rear traction motor w/ transaxle assembly. (Click here)
Remove the extension wire assembly from the rear traction motor w/ transaxle assembly. (Click here)
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Using a megohmmeter, measure the insulation resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| U - Shield shell | 10 MΩ or higher |
| V - Shield shell | 10 MΩ or higher |
| W - Shield shell | 10 MΩ or higher |
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Specified Condition |
| U - U | Below 1 Ω |
| V - V | Below 1 Ω |
| W - W | Below 1 Ω |
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| OK | ||
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