U1102

CRUISE CONTROL: DYNAMIC LASER CRUISE CONTROL SYSTEM: U1102: Lost Communication with Radar Sensor

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 presumed R information based on the signal from the steering wheel and yaw rate sensor.
The distance control ECU transmits the current vehicle speed and presumed R information to the laser sensor.





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

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





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






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

2. INSPECT DISTANCE CONTROL ECU





(a) Reconnect the distance control ECU connector.
(b) Turn the ignition switch on (IG).
(c) Measure the voltage according to the value(s) in the table below.
Standard voltage:





(d) Check the signal waveform between terminal LRRD (A20-23) of the distance control ECU and body ground.
OK:
A waveform similar to that in the illustration to the left is output.

HINT:
- Gauge set: 2 V/DIV, 5 ms/DIV
- Condition: Ignition switch on (IG)

NG -- REPLACE DISTANCE CONTROL ECU
OK -- REPLACE LASER SENSOR