Dynamic Radar Cruise Control System

CRUISE CONTROL: DYNAMIC RADAR CRUISE CONTROL SYSTEM: U0235: Lost Communication with Cruise Control Front Distance Range 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).






WIRING DIAGRAM





INSPECTION PROCEDURE
NOTICE:
- When the distance control ECU is replaced with a new one, initialization must be performed Installation.
- When the millimeter wave radar sensor is replaced with a new one, adjustment of the radar sensor beam axis must be performed Adjustments.

PROCEDURE

1. CHECK WIRE HARNESS (DISTANCE CONTROL ECU - MILLIMETER WAVE RADAR SENSOR)





(a) Disconnect the distance control ECU and millimeter wave radar sensor connectors.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPAIR OR REPLACE WIRE HARNESS AND CONNECTOR
OK -- Continue to next step.
2. CHECK DISTANCE CONTROL ECU





(a) Disconnect the millimeter wave radar sensor connector.
(b) Measure the Voltage according to the value(s) in the table below.
Standard voltage:






NG -- REPLACE DISTANCE CONTROL ECU
OK -- Continue to next step.
3. CHECK MILLIMETER WAVE RADAR SENSOR





(a) Reconnect the millimeter wave radar sensor connector.
(b) Measure the voltage according to the value(s) in the table below.
Standard voltage:










(c) Check the signal waveform between terminal LRDD (B8-3) 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)