Dtc B2271 Ignition Hold Monitor Malfunction

Engine. Lexus Gs430, Gs300. Uzs190 Grs190
3Uz-Fe Starting. Lexus Gs430, Gs300. Uzs190 Grs190

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT FUSE (AM2)

CHECK WIRE HARNESS (POWER SOURCE CONTROL ECU - BATTERY AND BODY GROUND)

DTC B2271 Ignition Hold Monitor Malfunction


DESCRIPTION

This DTC is output when the IG output circuits inside the power source control ECU are open or short.

DTC No.
DTC Detection Condition
Trouble Area
B2271
Hold circuit, IG1 relay actuation circuit or IG2 relay actuation circuit inside power source control ECU is open or short
  1. Power source control ECU
  1. AM2 fuse
  1. Wire harness

WIRING DIAGRAM


Lexus Gs430, Gs300. Uzs190 Grs190.3Uz-Fe Starting.Starting System. Dtc B2271 Ignition Hold Monitor Malfunction


INSPECTION PROCEDURE

1.INSPECT FUSE (AM2)

  1. Remove the AM2 fuse from the cowl side junction block RH.

  1. Measure the resistance of the fuse.

    Standard resistance:
    Below 1 Ω


NG
REPLACE FUSE
OK


2.CHECK WIRE HARNESS (POWER SOURCE CONTROL ECU - BATTERY AND BODY GROUND)


    Lexus Gs430, Gs300. Uzs190 Grs190.3Uz-Fe Starting.Starting System. Dtc B2271 Ignition Hold Monitor Malfunction

  1. Disconnect the L73 ECU connector.

  1. Measure the voltage and resistance of the wire harness side connector.

    Standard voltage:
    Tester Connection
    		Specified Condition
    L73-33 (AM1) - Body ground
    		10 to 14 V
    L73-12 (AM2) - Body ground
    		10 to 14 V
    Standard resistance:
    Tester Connection
    		Specified Condition
    L73-6 (GND2) - Body ground
    		10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK

REPLACE POWER SOURCE CONTROL ECU