Dtc U0235 Lost Communication With Cruise Control Front Distance Range Sensor

Lexus IS250 IS220d GSE20 ALE20 - CRUISE CONTROL

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK HARNESS AND CONNECTOR (DISTANCE CONTROL ECU - MILLIMETER WAVE RADAR SENSOR)

CHECK DISTANCE CONTROL ECU

CHECK MILLIMETER WAVE RADAR SENSOR

DTC U0235 Lost Communication with Cruise Control Front Distance Range Sensor

DESCRIPTION

The millimeter wave radar sensor and distance control ECU (cruise control ECU) transmit the data for general vehicle control and diagnosis function along the communication line. The millimeter wave radar sensor transmits information about the vehicle in front to the distance control ECU (cruise control ECU).

DTC No.DTC Detection ConditionTrouble Area
U0235The ECM detects a communication error signal (from the millimeter wave radar sensor to the distance control ECU) for 0.15 sec. or more while the dynamic radar cruise control is in operation
Communication circuit
Millimeter wave radar sensor
Distance control ECU (Cruise control ECU)

WIRING DIAGRAM

Dtc U0235 Lost Communication With Cruise Control Front Distance Range Sensor. CRUISE CONTROL. Lexus IS250 IS220d GSE20 ALE20

INSPECTION PROCEDURE

  • NOTICE:
When the distance control ECU is replaced with a new one, initialization must be performed .
When the millimeter wave radar sensor is replaced with a new one, adjustment of the radar sensor beam axis must be performed .
1.CHECK HARNESS AND CONNECTOR (DISTANCE CONTROL ECU - MILLIMETER WAVE RADAR SENSOR)
Dtc U0235 Lost Communication With Cruise Control Front Distance Range Sensor. CRUISE CONTROL. Lexus IS250 IS220d GSE20 ALE20

Disconnect the distance control ECU and millimeter wave radar sensor connectors.

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

  • Standard resistance:
  • Tester ConnectionConditionSpecified Condition
    J17-22 (LRDD) - B9-3 (LRDD)AlwaysBelow 1 Ω
    J17-13 (IGB) - B9-5 (IGB)AlwaysBelow 1 Ω
    J17-22 (LRDD) - Body groundAlways10 kΩ or higher
    J17-13 (IGB) - Body groundAlways10 kΩ or higher
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
2.CHECK DISTANCE CONTROL ECU
Dtc U0235 Lost Communication With Cruise Control Front Distance Range Sensor. CRUISE CONTROL. Lexus IS250 IS220d GSE20 ALE20

Disconnect the millimeter wave radar sensor connector.

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

  • Standard voltage:
  • Tester ConnectionConditionSpecified Condition
    J17-13 (IGB) - Body groundEngine switch on (IG)10 to 14 V
    J17-22 (LRDD) - J17-10 (SGND)Engine switch on (IG)4.5 to 5.5 V
NG
REPLACE DISTANCE CONTROL ECU
OK
3.CHECK MILLIMETER WAVE RADAR SENSOR
Dtc U0235 Lost Communication With Cruise Control Front Distance Range Sensor. CRUISE CONTROL. Lexus IS250 IS220d GSE20 ALE20

Reconnect the millimeter wave radar sensor connector.

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

  • Standard voltage:
  • Tester connectionConditionSpecified Condition
    B9-5 (IGB) - Body groundEngine switch on (IG)10 to 14 V
Dtc U0235 Lost Communication With Cruise Control Front Distance Range Sensor. CRUISE CONTROL. Lexus IS250 IS220d GSE20 ALE20

Check the signal waveform between terminal LRDD (B9-3) of the millimeter wave radar sensor and body ground.

  • OK:
  • A waveform similar to that in the illustration on the left is output.
  • HINT:
Gauge set: 2 V/DIV., 10 msec./DIV.
Condition: Engine switch on (IG)
NG
REPLACE MILLIMETER WAVE RADAR SENSOR
OK
END (INTERMITTENT PROBLEM IS PRESENT)