Dtc C1774 Low Battery Positive Voltage

Suspension & Axle. Lexus Gs430, Gs300. Uzs190 Grs190
Suspension Control. Lexus Gs430, Gs300. Uzs190 Grs190

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT BATTERY VOLTAGE

INSPECT FUSE (AIR SUS FUSE)

CHECK HARNESS AND CONNECTOR (B CIRCUIT)

CHECK HARNESS AND CONNECTOR (GND CIRCUIT)

RECONFIRM DTC

DTC C1774 Low Battery Positive Voltage


DESCRIPTION

  1. This circuit provides power to operate the absorber control ECU.
  2. This DTC is stored when the B terminal voltage deviates from the DTC detecting condition due to a malfunction in the power supply or a charging circuit such as the battery or alternator circuit, etc.

DTC No.
DTC Detection Condition
Trouble Area
C1774
The terminal B or battery voltage is below 10 V or above 16 V for 0.5 seconds.
  1. Battery
  2. Power source circuit
  3. Absorber control ECU

WIRING DIAGRAM


Lexus Gs430, Gs300. Uzs190 Grs190.Suspension Control.Adaptive Variable Suspension System. Dtc C1774 Low Battery Positive Voltage


INSPECTION PROCEDURE

NOTICE:
When replacing the absorber control ECU, check the acceleration sensor assembly signal after replacement (Click here).
HINT:
Check the condition of each related circuit connector before troubleshooting (Click here).
1.INSPECT BATTERY VOLTAGE

  1. Check the battery voltage.

    Voltage:
    10 to 14 V


NG
CHECK CHARGING SYSTEM
OK


2.INSPECT FUSE (AIR SUS FUSE)

  1. Remove the AIR SUS fuse from the cowl side J/B RH.

  1. Check continuity of AIR SUS fuse.

    OK:
    Continuity exists


NG
REPLACE AIR SUS FUSE
OK


3.CHECK HARNESS AND CONNECTOR (B CIRCUIT)


    Lexus Gs430, Gs300. Uzs190 Grs190.Suspension Control.Adaptive Variable Suspension System. Dtc C1774 Low Battery Positive Voltage

  1. Disconnect the absorber control ECU connector.

  1. Turn the engine switch on (IG).

  1. Measure the voltage according to the value(s) in the table below.

    Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    L72-1 (B) -
    Body ground
    		Engine switch on (IG)
    		10 to 14 V


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (B CIRCUIT)
OK


4.CHECK HARNESS AND CONNECTOR (GND CIRCUIT)


    Lexus Gs430, Gs300. Uzs190 Grs190.Suspension Control.Adaptive Variable Suspension System. Dtc C1774 Low Battery Positive Voltage

  1. Measure the resistance according to the value(s) in the table below.

    Resistance:
    Tester Connection
    		Specified Condition
    L72-4 (GND) - Body ground
    		Below 1 Ω


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT)
OK


5.RECONFIRM DTC

  1. Clear the DTC (Click here).

  1. Start the engine.

  1. Check if the same DTC is recorded (Click here).

    HINT:
    Reinstall the sensor, connectors, etc. and restore the vehicle to its prior condition before rechecking for DTCs.

    Result:

    Result
    		Proceed To
    DTC is output
    		A
    DTC is output (When troubleshooting accordance with the PROBLEM SYMPTOMS TABLE)
    		B
    DTC is not output
    		C


B
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

C
END
A

REPLACE ABSORBER CONTROL ECU