Cruise control

Lost Communication with Radar Sensor

7steps
~42min
2/5difficulty
Done 0 of 7

DTC U1102 Lost Communication with Radar Sensor

DESCRIPTION

The laser sensor and distance control ECU transmit the data for general vehicle control and diagnosis function along the communication line. The distance control ECU determines the curve radius information based on signals from the steering wheel and yaw rate sensor. The distance control ECU transmits the current vehicle speed and curve radius information to the laser sensor.

DTC No.

DTC Detection Condition

Trouble Area

U1102

The ECM detects a communication error signal (from the distance control ECU to the laser sensor) for 0.15 sec. or more while the dynamic laser cruise control is in operation
  • Communication circuit
  • Laser sensor
  • Distance control ECU (Cruise control ECU)

WIRING DIAGRAM

WIRING DIAGRAM

INSPECTION PROCEDURE

NOTICE:

  • When the distance control ECU is replaced with a new one, initialization must be performed.
  • When the laser sensor is replaced with a new one, adjustment of the laser sensor beam axis must be performed

1 CHECK HARNESS AND CONNECTOR (DISTANCE CONTROL ECU - LASER SENSOR)

CHECK HARNESS AND CONNECTOR (DISTANCE CONTROL ECU - LASER SENSOR)
  1. Disconnect the D2 distance control ECU connector and L1 laser sensor connector.
  2. Measure the resistance according to the value(s) in the table below.

Standard resistance

Standard resistance

2 CHECK DISTANCE CONTROL ECU

CHECK DISTANCE CONTROL ECU
  1. Reconnect the D2 distance control ECU connector.
  2. Measure the voltage according to the value(s) in the table below.

Standard voltage

Standard voltage
  1. Reconnect the L1 laser sensor connector.

3 CHECK DTC OUTPUT

  1. Clear the DTCs.
  2. Turn the ignition switch to the ON position.
  3. Check if the same DTC is recorded

Result

Result

END (INTERMITTENT PROBLEM IS PRESENT)

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