DTC U1102: Lost Communication with Radar Sensor: Procedure

1. Disconnect the distance control ECU connector.
2. Disconnect the millimeter wave radar sensor connector.
   Fig 1: Identifying Terminals Of Distance Control ECU And Millimeter Wave Radar Sensor Connectors

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   J17-23 (LRRD) - B9-4 (LRRD)	Always	Below 1 Ω
   J17-13 (IGB) - B9-5 (IGB)	Always	Below 1 Ω
   J17-23 (LRRD) - Body ground	Always	10 kΩ or higher
   J17-13 (IGB) - Body ground	Always	10 kΩ or higher

4. Reconnect the distance control ECU connector.
5. Reconnect the millimeter wave radar sensor connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Replace the distance control ECU. Refer to REMOVAL .
2. Initialize the distance control ECU. Refer to INSTALLATION - Step 3 .

NEXT: Go to next step 

1. Clear the DTCs. Refer to DTC CHECK / CLEAR .
2. Turn the cruise control main switch on.
3. Drive the vehicle at a speed for which cruise control operation is possible.
4. Check if the same DTC is recorded. Refer to DTC CHECK / CLEAR .

   Result

   Result	Proceed to
   DTC U1102 is not output	A
   DTC U1102 is output	B

B → See step   4 

A → END