Nissan Xterra. Manual - part 316

EC-390

< DTC/CIRCUIT DIAGNOSIS >

[VQ40DE]

P1553 BATTERY CURRENT SENSOR

Refer to 

EC-152, "Ground Inspection"

.

OK or NG

OK

>> GO TO 2.

NG

>> Repair or replace ground connections.

2.

CHECK BATTERY CURRENT SENSOR POWER SUPPLY CIRCUIT

1. Disconnect battery current sensor harness connector.

2. Turn ignition switch ON.

3. Check voltage between battery current sensor terminal 1 and

ground with CONSULT or tester.

OK or NG

OK

>> GO TO 4.

NG

>> GO TO 3.

3.

DETECT MALFUNCTIONING PART

Check the following.

• Harness connectors E5, F14

• Harness for open or short between battery current sensor and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

4.

CHECK BATTERY CURRENT SENSOR GROUND CIRCUIT FOR OPEN AND SHORT

1. Turn ignition switch OFF.

2. Disconnect ECM harness connector.

3. Check harness continuity between battery current sensor terminal 2 and ECM terminal 68.

4. Also check harness for short to ground and short to power.
OK or NG

OK

>> GO TO 6.

NG

>> GO TO 5.

5.

DETECT MALFUNCTIONING PART

Check the following.

• Harness connectors E5, F14

• Harness for open or short between battery current sensor and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

6.

CHECK BATTERY CURRENT SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1. Check harness continuity between battery current sensor terminal 3 and ECM terminal 66.

BBIA0539E

Voltage: Approximately 5V

BBIA0582E

Continuity should exist.

Continuity should exist.

P1553 BATTERY CURRENT SENSOR

EC-391

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2. Also check harness for short to ground and short to power.
OK or NG

OK

>> GO TO 8.

NG

>> GO TO 7.

7.

DETECT MALFUNCTIONING PART

Check the following.

• Harness connectors E5, F14

• Harness for open or short between battery current sensor and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

8.

CHECK BATTERY CURRENT SENSOR

Refer to 

EC-391, "Component Inspection"

.

OK or NG

OK

>> GO TO 9.

NG

>> Replace battery negative cable assembly.

9.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-40, "Intermittent Incident"

.

>> INSPECTION END

Component Inspection

INFOID:0000000009484129

BATTERY CURRENT SENSOR

1. Reconnect harness connectors disconnected.
2. Disconnect battery negative cable.
3. Install jumper cable between battery negative terminal and body

ground.

4. Turn ignition switch ON.
5. Check voltage between ECM terminal 66 (battery current sensor

signal) and ground.

6. If NG, replace battery negative cable assembly.

Voltage: Approximately 2.5V

BBIA0588E

EC-392

< DTC/CIRCUIT DIAGNOSIS >

[VQ40DE]

P1554 BATTERY CURRENT SENSOR

P1554 BATTERY CURRENT SENSOR

Component Description

INFOID:0000000009484130

The power generation voltage variable control enables fuel con-

sumption to be decreased by reducing the engine load which is

caused by the power generation of the generator. The battery cur-

rent sensor is installed to the battery cable at the negative terminal.

The sensor measures the charging/discharging current of the bat-

tery. Based on the sensor signal, ECM judges whether or not the

power generation voltage variable control is performed. When per-

forming the power generation voltage variable control, ECM calcu-

lates the target power generation voltage based on the sensor

signal. And ECM sends the calculated value as the power genera-

tion command value to IPDM E/R. For the details of the power gen-

eration voltage variable control, refer to 

CHG-9, "System

Description"

.

CAUTION:

Never connect the electrical component or the ground wire directly to the battery terminal. The con-

nection causes the malfunction of the power generation voltage variable control, and then the battery

discharge may occur.

On Board Diagnosis Logic

INFOID:0000000009484131

The MIL will not illuminate for this diagnosis.

NOTE:

If DTC P1554 is displayed with DTC P0643, first perform the trouble diagnosis for DTC P0643. Refer to

EC-366

.

Overall Function Check

INFOID:0000000009484132

Use this procedure to check the overall function of the battery current sensor circuit. During this check, a 1st

trip DTC might not be confirmed.

TESTING CONDITION:

• Before performing the following procedure, confirm that battery voltage is more than 12.8V at idle.

• Before performing the following procedure, confirm that all load switches and A/C switch are turned

OFF.

 WITH CONSULT

1. Start engine and let it idle.
2. Select “BAT CUR SEN” in “DATA MONITOR” mode with CONSULT.
3. Check “BAT CUR SEN” indication for 10 seconds.

“BAT CUR SEN” should be above 2,300mV at least once.

4. If NG, go to 

EC-392, "Diagnosis Procedure"

.

 WITH GST

1. Start engine and let it idle.
2. Check voltage between ECM terminal 66 (battery current sensor signal) and ground for 10 seconds.

The voltage should be above 2.3V at least once.

3. If NG, go to 

EC-392, "Diagnosis Procedure"

.

Diagnosis Procedure

INFOID:0000000009484133

1.

CHECK GROUND CONNECTIONS

BBIA0582E

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P1554
1554

Battery current sensor perfor-
mance

The output voltage of the battery current 
sensor is lower than the specified value 
while the battery voltage is high enough.

• Harness or connectors

(The sensor circuit is open or shorted.)

• Battery current sensor

P1554 BATTERY CURRENT SENSOR

EC-393

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1. Turn ignition switch OFF.

2. Loosen and retighten three ground screws on the body.

Refer to 

EC-152, "Ground Inspection"

.

OK or NG

OK

>> GO TO 2.

NG

>> Repair or replace ground connections.

2.

CHECK BATTERY CURRENT SENSOR POWER SUPPLY CIRCUIT

1. Disconnect battery current sensor harness connector.

2. Turn ignition switch ON.

3. Check voltage between battery current sensor terminal 1 and

ground with CONSULT or tester.

OK or NG

OK

>> GO TO 4.

NG

>> GO TO 3.

3.

DETECT MALFUNCTIONING PART

Check the following.

• Harness connectors E5, F14

• Harness for open or short between battery current sensor and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

4.

CHECK BATTERY CURRENT SENSOR GROUND CIRCUIT FOR OPEN AND SHORT

1. Turn ignition switch OFF.

2. Disconnect ECM harness connector.

3. Check harness continuity between battery current sensor terminal 2 and ECM terminal 68.

4. Also check harness for short to ground and short to power.
OK or NG

OK

>> GO TO 6.

NG

>> GO TO 5.

5.

DETECT MALFUNCTIONING PART

Check the following.

• Harness connectors E5, F14

• Harness for open or short between battery current sensor and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

6.

CHECK BATTERY CURRENT SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1. Check harness continuity between battery current sensor terminal 3 and ECM terminal 66.

BBIA0539E

Voltage: Approximately 5V

BBIA0582E

Continuity should exist.