Infiniti FX35, FX50 (S51). Manual - part 717

P1553 BATTERY CURRENT SENSOR

EC-409

< DTC/CIRCUIT DIAGNOSIS >

[VQ35HR]

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11.

CHECK BATTERY CURRENT SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1.

Check the continuity between battery current sensor harness connector and ECM harness connector.

2.

Also check harness for short to ground and short to power.

Is the inspection result normal?

YES

>> GO TO 13.

NO

>> GO TO 12.

12.

DETECT MALFUNCTIONING PART

Check the following.
• Harness connectors F1, E3
• Harness for open or short between battery current sensor and ECM

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

13.

CHECK BATTERY CURRENT SENSOR

Refer to 

EC-409, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 14.

NO

>> Replace battery negative cable assembly.

14.

CHECK INTERMITTENT INCIDENT

Refer to 

GI-36, "Intermittent Incident"

.

>> INSPECTION END

Component Inspection

INFOID:0000000005237014

1.

CHECK BATTERY CURRENT SENSOR

1.

Turn ignition switch OFF.

2.

Reconnect harness connectors disconnected.

3.

Disconnect battery negative cable (1).

4.

Install jumper cable (A) between battery negative terminal and
body ground.

5.

Turn ignition switch ON.

6.

Check the voltage between ECM harness connector terminals
as follows.

Before measuring the terminal voltage, confirm that the battery is fully charged. Refer to 

PG-3, "How to Handle Battery"

.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace battery negative cable assembly.

Battery current sensor

ECM

Continuity

Connector

Terminal

Connector

Terminal

E21

3

F102

91

Existed

: To body ground

ECM

Voltage (V)

Connector

+

–

Terminal

Terminal

F102

91

(Battery current sensor signal)

95

Approx. 2.5

JMBIA1512ZZ

EC-410

< DTC/CIRCUIT DIAGNOSIS >

[VQ35HR]

P1554 BATTERY CURRENT SENSOR

P1554 BATTERY CURRENT SENSOR

Description

INFOID:0000000005237015

The power generation voltage variable control enables fuel consumption to be decreased by reducing the
engine load which is caused by the power generation of the generator. The battery current 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 performing the power generation voltage variable control, ECM calculates the target power
generation voltage based on the sensor signal. And ECM sends the calculated value as the power generation
command value to IPDM E/R. For the details of the power generation voltage variable control, refer to 

CHG-8,

"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 battery dis-
charge may occur.

DTC Logic

INFOID:0000000005237016

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PERFORM COMPONENT FUNCTION CHECK

Perform component function check. Refer to 

EC-410, "Component Function Check"

.

NOTE:
Use component function check to check the overall function of the battery current sensor circuit. During this
check, a 1st trip DTC might not be confirmed.
Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Go to 

EC-411, "Diagnosis Procedure"

.

Component Function Check

INFOID:0000000005237017

1.

PRECONDITIONING

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

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P1554

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

(Battery current sensor circuit is open 
or shorted.)
[Crankshaft position (CKP) sensor cir-
cuit is shorted.]
[Camshaft position (CMP) sensor 
(bank 2) circuit is shorted.]
Exhaust valve timing (EVT) control po-
sition sensor (bank 2) circuit is short-
ed.]
[Accelerator pedal position (APP) sen-
sor 2 circuit is shorted.]
(EVAP control system pressure sensor 
circuit is shorted.)
(Refrigerant pressure sensor circuit is 
shorted.)

• Battery current sensor
• CKP sensor
• CMP sensor (bank 2)
• EVT control position sensor (bank 2)
• APP sensor
• EVAP control system pressure sensor
• Refrigerant pressure sensor

P1554 BATTERY CURRENT SENSOR

EC-411

< DTC/CIRCUIT DIAGNOSIS >

[VQ35HR]

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

OFF.

>> GO TO 2.

2.

PERFORM COMPONENT FUNCTION CHECK

With CONSULT-III

1.

Start engine and let it idle.

2.

Select “BAT CUR SEN” in “DATA MONITOR” mode with CONSULT-III.

3.

Check “BAT CUR SEN” indication for 10 seconds.
“BAT CUR SEN” should be above 2,300 mV at least once.

Without CONSULT-III

1.

Start engine and let it idle.

2.

Check the voltage between ECM harness connector terminals as follows.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Go to 

EC-411, "Diagnosis Procedure"

.

Diagnosis Procedure

INFOID:0000000005237018

1.

CHECK GROUND CONNECTION

1.

Turn ignition switch OFF.

2.

Check ground connection M95. Refer to Ground Inspection in 

GI-39, "Circuit Inspection"

.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Repair or replace ground connection.

2.

CHECK BATTERY CURRENT SENSOR POWER SUPPLY CIRCUIT-I

1.

Disconnect battery current sensor harness connector.

2.

Turn ignition switch ON.

3.

Check the voltage between battery current sensor harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 9.

NO

>> GO TO 3.

3.

CHECK BATTERY CURRENT SENSOR POWER SUPPLY CIRCUIT-II

1.

Turn ignition switch OFF.

2.

Disconnect ECM harness connector.

3.

Check the continuity between battery current sensor harness connector and ECM harness connector.

Is the inspection result normal?

ECM

Voltage (V)

Connector

+

–

Terminal

Terminal

F102

91

(Battery current sensor signal)

95

Above 2.3 at least once

Battery current sensor

Ground

Voltage (V)

Connector

Terminal

E21

1

Ground

Approx. 5

Battery current sensor

ECM

Continuity

Connector

Terminal

Connector

Terminal

E21

1

F102

64

Existed

EC-412

< DTC/CIRCUIT DIAGNOSIS >

[VQ35HR]

P1554 BATTERY CURRENT SENSOR

YES

>> GO TO 5.

NO

>> GO TO 4.

4.

DETECT MALFUNCTIONING PART

Check the following.
• Harness connectors F1, E3
• Harness for open between battery current sensor and ECM

>> Repair open circuit.

5.

CHECK SENSOR POWER SUPPLY CIRCUIT

Check harness for short to power and short to ground, between the following terminals.

Is the inspection result normal?

YES

>> GO TO 6.

NO

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

6.

CHECK COMPONENTS

Check the following.
• CKP sensor (Refer to 

EC-271, "Component Inspection"

.)

• CMP sensor (bank 2) (Refer to 

EC-277, "Component Inspection"

.)

• EVT control position sensor (bank 2) (Refer to 

EC-369, "Component Inspection"

.)

• EVAP control system pressure sensor (Refer to 

EC-313, "Component Inspection"

.)

• Refrigerant pressure sensor (Refer to 

HAC-84, "Diagnosis Procedure"

.)

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Replace malfunctioning component.

7.

CHECK APP SENSOR

Refer to 

EC-444, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 14.

NO

>> GO TO 8.

8.

REPLACE ACCELERATOR PEDAL ASSEMBLY

1.

Replace accelerator pedal assembly.

2.

Go to 

EC-445, "Special Repair Requirement"

.

>> INSPECTION END

9.

CHECK BATTERY CURRENT SENSOR GROUND CIRCUIT FOR OPEN AND SHORT

1.

Turn ignition switch OFF.

ECM

Sensor

Connector

Terminal

Name

Connector

Terminal

F101

46

Crankshaft position (CKP) sensor

F2

1

F102

64

Camshaft position (CMP) sensor (bank 2)

F18

1

Exhaust valve timing (EVT) control posi-
tion sensor (bank 2)

F19

1

Battery current sensor

E21

1

M107

103

Accelerator pedal position (APP) sensor

E112

(Without ICC)

6

E116

(With ICC)

3

107

EVAP control system pressure sensor

B252

3

111

Refrigerant pressure sensor

E77

3