Nissan Altima HL32 Hybrid. Manual - part 597

P0A09-265

HBC-137

< COMPONENT DIAGNOSIS >

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P0A09-265

Description

INFOID:0000000004211792

The hybrid vehicle converter (DC/DC converter) converts the DC 244.8 V of the HV battery into DC 12 V in

order to supply power to areas such as the vehicle's lighting, audio, and ECU systems. In addition, it charges

the auxiliary battery.

A transistor bridge circuit initially converts DC 244.8 V into alternating current, and a transformer lowers its

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

The hybrid vehicle converter (DC/DC converter) controls the output voltage in order to keep a constant voltage

at the terminals of the auxiliary battery.

The hybrid vehicle control ECU uses the NODD signal line to transmit a stop command to the hybrid vehicle

converter (DC/DC converter) and receive signals indicating the normal or abnormal condition of the 12 V

charging system.

If the vehicle is being driven with an inoperative hybrid vehicle converter (DC/DC converter), the voltage of the

auxiliary battery will drop, which will prevent the continued operation of the vehicle. Therefore, the hybrid vehi-

cle control ECU monitors the operation of the hybrid vehicle converter (DC/DC converter) and alerts the driver

if it detects a malfunction.

JMCIA0093GB

HBC-138

< COMPONENT DIAGNOSIS >

P0A09-265

DTC Logic

INFOID:0000000004211793

DTC DETECTION LOGIC

Diagnosis Procedure

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1.

PRECONDITIONING

• Before inspecting the high-voltage system or disconnecting the low voltage connector of the inverter with

converter assembly, take safety precautions such as wearing insulated gloves and removing the service

plug grip to prevent electrical shocks. After removing the service plug grip, put it in your pocket to prevent

other technicians from accidentally reconnecting it while you are working on the high-voltage system.

• After disconnecting the service plug grip, wait for at least 10 minutes before touching any of the high-voltage

connectors or terminals.

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

converter assembly. 

>> GO TO 2.

2.

CHECK DTC OUTPUT (HYBRID SYSTEM)

1. Turn ignition switch ON.

2. Check DTC.
Is DTC P0AE6-225 detected?

YES

>> Go to inspection procedure relevant to output DTC (P0AE6-225).

NO

>> GO TO 3.

3.

CHECK CONNECTOR CONNECTION CONDITION (HYBRID VEHICLE CONTROL ECU CONNECTOR)

JMCIA0139GB

DTC No.

INF code

Trouble diagnosis name

DTC detecting condition

Possible cause

P0A09

265

DC/DC Converter Status Cir-
cuit Low Input

Open or short to GND in the hybrid 
vehicle converter (DC/DC converter) 
(NODD) signal line

• Wire harness or connector
• Hybrid vehicle converter (DC/DC 

converter)

• Hybrid vehicle control ECU

P0A09-265

HBC-139

< COMPONENT DIAGNOSIS >

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See 

HBC-109, "Diagnosis Procedure"

.

OK or NG

OK

>> GO TO 4.

NG

>> Connect securely.

4.

CHECK CONNECTOR CONNECTION CONDITION (BATTERY PACK WIRE CONNECTOR)

See 

HBC-140, "Diagnosis Procedure"

.

OK or NG

OK

>> GO TO 5.

NG

>> COnnect securely.

5.

CHECK HARNESS AND CONNECTOR (RESISTANCE VALUE OF NODD INSIDE HYBRID VEHICLE

CONTROL ECU)

See 

HBC-132, "Diagnosis Procedure"

.

OK or NG

OK

>> GO TO 6.

NG

>> GO TO 8.

6.

CHECK CONNECTOR CONNECTION CONDITION (HYBRID VEHICLE CONVERTER CONNECTOR)

See 

HBC-140, "Diagnosis Procedure"

.

OK or NG

OK

>> GO TO 7.

NG

>> Connect securely.

7.

CHECK HARNESS AND CONNECTOR (BATTERY PACK WIRE CONNECTOR - HYBRID VEHICLE CON-

VERTER)

See 

HBC-132, "Diagnosis Procedure"

.

OK or NG

OK

>> Replace hybrid vehicle converter (See 

HBC-644, "Removal and Installation"

).

NG

>> Repair or replace harness or connector.

8.

CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - BATTERY PACK WIRE

CONNECTOR)

See 

HBC-132, "Diagnosis Procedure"

.

OK or NG

OK

>> Replace hybrid vehicle control ECU (See 

HBC-644, "Removal and Installation"

).

NG

>> Repair or replace harness or connector.

HBC-140

< COMPONENT DIAGNOSIS >

P0A09-591

P0A09-591

Description

INFOID:0000000004211795

The hybrid vehicle converter (DC/DC converter) controls output voltage based on voltage switching signals

sent from the hybrid vehicle control ECU.

DTC Logic

INFOID:0000000004211796

DTC DETECTION LOGIC

Diagnosis Procedure

INFOID:0000000004211797

1.

PRECONDITIONING

• Before inspecting the high-voltage system or disconnecting the low voltage connector of the inverter with

converter assembly, take safety precautions such as wearing insulated gloves and removing the service

plug grip to prevent electrical shocks.

After removing the service plug grip, put it in your pocket to prevent other technicians from accidentally

reconnecting it while you are working on the high-voltage system.

• After disconnecting the service plug grip, wait for at least 10 minutes before touching any of the high-voltage

connectors or terminals.

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

converter assembly.

>> GO TO 2.

2.

CHECK DTC OUTPUT (HYBRID SYSTEM)

1. Turn ignition switch ON.

2. Check DTC.
Is DTC P0AE6-225 detected?

YES

>> Go to inspection procedure relevant to output DTC (P0AE6-225).

NO

>> GO TO 3.

3.

CHECK CONNECTOR CONNECTION CONDITION (HYBRID VEHICLE CONTROL ECU CONNECTOR)

See 

HBC-109, "Diagnosis Procedure"

.

OK or NG

JMCIA0140GB

DTC No.

INF code

Trouble diagnosis name

DTC detecting condition

Possible cause

P0A09

591

DC/DC Converter Status 
Circuit Low Input

Hybrid vehicle converter (DC/DC 
converter) voltage switching 
(VLO) signal circuit malfunction 
(Open or short to GND)

• Hybrid vehicle converter (DC/DC converter)
• Hybrid vehicle control ECU
• Wire harness or connector