Dtc P1550 Battery Current Sensor Circuit

Engine. Lexus Is250, Is220D. Gse20 Ale20
2Ad-Fhv Engine Control System. Lexus Is250, Is220D. Gse20 Ale20

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT BATTERY CURRENT SENSOR ASSEMBLY

CHECK HARNESS AND CONNECTOR (BATTERY CURRENT SENSOR - ECM)

DTC P1550 Battery Current Sensor Circuit

DTC P1551 Battery Current Sensor Circuit Low

DTC P1552 Battery Current Sensor Circuit High


DESCRIPTION

The battery current sensor installed on the positive battery terminal detects the amount of current supplied from the alternator.
Lexus Is250, Is220D. Gse20 Ale20.2Ad-Fhv Engine Control System.Ecd System. Dtc P1550 Battery Current Sensor Circuit
The battery current sensor changes current to voltage and outputs that voltage. The battery current sensor changes current at the positive battery terminal to voltage and sends it to the ECM. The ECM controls the voltage of the alternator based on the signals from the battery current sensor.

DTC No.
DTC Detection Condition
Trouble Area
P1550
The following condition continues for 10 seconds or more with the engine switch on (IG).
(1 trip detection logic)
  1. Difference between the maximum and minimum current values of the battery current sensor is 1 A or less
  1. Open or short in battery current sensor circuit
  2. Battery current sensor
  3. ECM
P1551
Battery current sensor output value is 0.2 V or less for 0.5 seconds or more with the engine switch on (IG).
(1 trip detection logic)
  1. Short in battery current sensor circuit
  2. Battery current sensor
  3. ECM
P1552
Battery current sensor output value is 4.8 V or more for 0.5 seconds or more with the engine switch on (IG).
(1 trip detection logic)
  1. Open in battery current sensor circuit
  2. Battery current sensor
  3. ECM

WIRING DIAGRAM


Lexus Is250, Is220D. Gse20 Ale20.2Ad-Fhv Engine Control System.Ecd System. Dtc P1550 Battery Current Sensor Circuit


INSPECTION PROCEDURE

NOTICE:
After replacing the ECM, the new ECM needs registration (Click here) and initialization (Click here).
1.INSPECT BATTERY CURRENT SENSOR ASSEMBLY


    Lexus Is250, Is220D. Gse20 Ale20.2Ad-Fhv Engine Control System.Ecd System. Dtc P1550 Battery Current Sensor Circuit

  1. Disconnect the A48 battery current sensor connector.

  1. Measure the resistance of the battery current sensor.

    Standard resistance:
    Tester Connection
    		Specified Condition
    VC5 (3) - E2 (2)
    		3 to 6 or 0.7 to 8 kΩ
    VC5 (3) - IB (1)
    		0.2 to 0.3 kΩ
    IB (1) - E2 (2)
    		1.5 to 8 or 3 to 6 kΩ
    HINT:
    The resistance differs according to the tester type.


NG
REPLACE BATTERY CURRENT SENSOR ASSEMBLY
OK


2.CHECK HARNESS AND CONNECTOR (BATTERY CURRENT SENSOR - ECM)


    Lexus Is250, Is220D. Gse20 Ale20.2Ad-Fhv Engine Control System.Ecd System. Dtc P1550 Battery Current Sensor Circuit

  1. Check the harness and the connectors between the ECM and the battery current sensor.

    1. Disconnect the A48 battery current sensor connector.

    2. Disconnect the E59 ECM connectors.

    3. Measure the resistance of the wire harness side connectors.

      Standard resistance (Check for open):
      Tester Connection
      		Specified Condition
      IB (A48-1) - IB (E59-116)
      		Below 1 Ω
      VC5 (A48-3) - VCIB (E59-70)
      		Below 1 Ω
      E2 (A48-2) - EIB (E59-93)
      		Below 1 Ω
      Standard resistance (Check for short):
      Tester Connection
      		Specified Condition
      IB (A48-1) or IB (E59-116) - Body ground
      		10 kΩ or higher
      VC5 (A48-3) or VCIB (E59-70) - Body ground
      		10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE ECM