DTC U1232: Lost Communication With Rear/Side Radar Control Module

DTC detecting condition: 

No data is received from radar sensor.

Trouble symptom: 

Cooperation control of radar sensor does not operate properly.

1. CHECK CAN COMMUNICATION HARNESS. 

   Perform the basic diagnostic procedure to check for fault in CAN communication harness. Ref. to LAN SYSTEM (DIAGNOSTICS)>BASIC DIAGNOSTIC PROCEDURE .

   Was the basic diagnostic procedure performed up to step 7?

   Yes  : Go to  2.

   No  : Perform the basic diagnostic procedure. Ref. to LAN SYSTEM (DIAGNOSTICS)>BASIC DIAGNOSTIC PROCEDURE .

2. CHECK DTC (OTHER THAN U-CODE). 

   Check the displayed DTC.

   Is DTC other than U*** displayed? (Current malfunction)

   Yes  : Perform the diagnosis for DTCs other than the displayed U-code.

   No  : Go to  3.

3. CHECK DTC. 

   Check the displayed DTC.

   Is DTC U1232 displayed? (Current malfunction)

   Yes  : Go to  4.

   No  : Go to  6.

4. CHECK DTC. 
   1. Check CAN communication circuit. Ref. to LAN SYSTEM (DIAGNOSTICS)>CAN COMMUNICATION CIRCUIT CHECK .
   2. Using the Subaru Select Monitor, read all DTCs. Ref. to LAN SYSTEM (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)>OPERATION .

   Is DTC U1232 displayed? (Current malfunction)

   Yes  : Go to  5.

   No  : Go to  6.

5. CHECK DTC. 

   Using the Subaru Select Monitor, read all DTCs. Ref. to LAN SYSTEM (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)>OPERATION .

   Is DTC U1232 detected in several modules? (Current malfunction)

   Yes  : Replace the radar sensor LH. Ref. to BLIND SPOT DETECTION/REAR CROSS TRAFFIC ALERT>RADAR SENSOR .

   No  : Replace the module that the DTC has been detected.

6. CHECK HARNESS. 
   1. Shake the harness, and check for poor contact.
   2. Using the Subaru Select Monitor, read all DTCs. Ref. to LAN SYSTEM (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)>OPERATION .

   Is DTC U1232 displayed? (Current malfunction)

   Yes  : Repair the poor contact of harness, or replace the harness.

   No  : Go to  7.

7. CHECK CONNECTOR. 

   Check the connector used for high speed CAN for poor contact.

   Is there poor contact of connector?

   Yes  : Repair the connector that has poor contact, or replace harness.

   No  : It is possible that temporary poor communication occurs. Delete the DTC.