Up to 08/2009

CRUISE CONTROL: DYNAMIC RADAR CRUISE CONTROL SYSTEM: U1102: Lost Communication with Radar Sensor
U1102 - Lost Communication with Radar Sensor

DESCRIPTION

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





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
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 HARNESS AND CONNECTOR (DRIVING SUPPORT ECU - MILLIMETER WAVE RADAR SENSOR)

(a) Disconnect the driving support ECU and millimeter wave radar sensor connectors.

Text in Illustration









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

Standard Resistance:





(c) Reconnect the driving support ECU and millimeter wave radar sensor connectors.

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

2. CHECK HARNESS AND CONNECTOR (MILLIMETER WAVE RADAR SENSOR POWER SOURCE CIRCUIT)

(a) Disconnect the millimeter wave radar sensor connector.





(b) Turn the engine switch on (IG).

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

Standard Voltage:





Text in Illustration





(d) Reconnect the millimeter wave radar sensor connector.

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

3. CHECK HARNESS AND CONNECTOR (MILLIMETER WAVE RADAR SENSOR - BODY GROUND)

(a) Disconnect the millimeter wave radar sensor connector.

Text in Illustration









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

Standard Resistance:





(c) Reconnect the millimeter wave radar sensor connector.

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

4. CHECK MILLIMETER WAVE RADAR SENSOR

(a) Disconnect the driving support ECU connector.





(b) Turn the engine switch on (IG).

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

Standard Voltage:





Text in Illustration





(d) Reconnect the driving support ECU connector.

NG -- REPLACE MILLIMETER WAVE RADAR SENSOR Components
OK -- Continue to next step.

5. REPLACE DRIVING SUPPORT ECU

(a) Replace the driving support ECU Components.

NEXT -- Continue to next step.

6. CHECK DTC OUTPUT

(a) Clear the DTCs Dynamic Radar Cruise Control System.

(b) Perform the following to make sure that the DTC detection conditions are met.

HINT
If the detection conditions are not met, the malfunction cannot be detected.

(1) Drive the vehicle at a speed of 50 km/h (31 mph) or more.

(2) Turn the cruise control main switch on.

(c) Check for DTCs Dynamic Radar Cruise Control System.

Result:





B -- REPLACE MILLIMETER WAVE RADAR SENSOR Components

A -- END