Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual: Linear Solenoid Circuit (C1298)

Lexus RX (RX 350L, RX450h) 2016-2026 Repair Manual / Drivetrain / Mf1a (transfer / 4wd / Awd) / Dynamic Torque Control Awd System / Linear Solenoid Circuit (C1298)

DESCRIPTION

The 4WD ECU assembly receives signals from each sensor. The signals are used to control the clutch fluid pressure to vary the distribution of torque in accordance with the driving conditions.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

C1298

Linear Solenoid Circuit

When all of the following continue for 1 second or more:

  • The voltage at terminal IG1 is 9.5 V or more.
  • The target current for the 4WD linear solenoid (electro magnetic control coupling sub-assembly) is either 0 A or 0.8 A or more.
  • An open or short is detected in the linear solenoid circuit.
  • Wire harness and connector
  • 4WD linear solenoid (Electro magnetic control coupling sub-assembly)
  • 4WD ECU assembly

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

When the 4WD ECU assembly is replaced with a known good one from another vehicle, it is necessary to perform calibration.

Click here

HINT:

Check the condition of each related circuit connector before troubleshooting.

Click here

PROCEDURE

1.

CHECK HARNESS AND CONNECTOR (4WD ECU ASSEMBLY - ELECTRO MAGNETIC CONTROL COUPLING SUB-ASSEMBLY)

(a) Disconnect the R10 4WD ECU assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

R10-2 (SLC+) - R10-1 (SLC-)

20°C (68°F)

1.75 to 2.15 Ω

R10-2 (SLC+) - Body ground

Always

10 kΩ or higher

R10-1 (SLC-) - Body ground

Always

10 kΩ or higher
OK

REPLACE 4WD ECU ASSEMBLY

NG

2.

INSPECT ELECTRO MAGNETIC CONTROL COUPLING SUB-ASSEMBLY

(a) Disconnect the T4 4WD linear solenoid (electro magnetic control coupling sub-assembly) connector.

*a

Component without harness connected

(4WD Linear Solenoid (Electro Magnetic Control Coupling Sub-assembly))

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

1 (BSF) - 2 (SLC)

20°C (68°F)

1.75 to 2.15 Ω

1 (BSF) - Body ground

Always

10 kΩ or higher

2 (SLC) - Body ground

Always

10 kΩ or higher
OK

REPAIR OR REPLACE HARNESS OR CONNECTOR
NG

REPLACE ELECTRO MAGNETIC CONTROL COUPLING SUB-ASSEMBLY

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