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Home >> Subaru >> 2017 >> WRX STI >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Communication Devices >> LAN Communication System (Diagnostics) >> Diagnostic Procedure with Diagnostic Trouble Code (DTC) >> DTC U0327 Software Incompatibility With Vehicle Security Control Module
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DTC U0327 Software Incompatibility With Vehicle Security Control Module

DTC DETECTING CONDITION: 

No data is received from keyless access Control Module.

TROUBLE SYMPTOM: 

Cooperation control of keyless access does not operate properly.

Step Check Yes No
1 CHECK CAN COMMUNICATION HARNESS. 
Perform the basic diagnostic procedure to check for fault in CAN communication harness. <Ref. to BASIC DIAGNOSTIC PROCEDURE .>
Was the basic diagnostic procedure performed up to step 7? Go to step . Perform the basic diagnostic procedure. <Ref. to BASIC DIAGNOSTIC PROCEDURE .>
2 CHECK DTC (OTHER THAN U-CODE). 
Check the displayed DTC.
Are DTCs other than U*** displayed? Perform the diagnosis for DTCs other than the displayed U-code. Go to step .
3 CHECK DTC (CURRENT MALFUNCTION). 
Check the displayed DTC.
Is U0327 a current malfunction? Go to step . Go to step .
4 CHECK DTC (CURRENT MALFUNCTION). 
  1. Check CAN communication circuit. <Ref. to CAN COMMUNICATION CIRCUIT CHECK .>
  2. Read the DTC using Subaru Select Monitor. <Ref. to READ DIAGNOSTIC TROUBLE CODE (DTC) .>
Is U0327 a current malfunction? Go to step . Go to step .
5 CHECK DTC (CURRENT MALFUNCTION). 
Using the Subaru Select Monitor, read DTC of all the systems. <Ref. to READ DIAGNOSTIC TROUBLE CODE (DTC) .>
Is the smart data no-receive detected in several modules? Replace the keyless access Control Module. <Ref. to Keyless Access Control Module .> Replace the module that the DTC has been detected.
6 CHECK HARNESS. 
  1. Shake the harness, and check for poor contact.
  2. Read the DTC using Subaru Select Monitor. <Ref. to READ DIAGNOSTIC TROUBLE CODE (DTC) .>
Is U0327 a current malfunction? Repair the poor contact of harness, or replace the harness. Go to step .
7 CHECK CONNECTOR. 
Check the connector used for high speed CAN for poor contact.
Is there poor contact of connector? Repair the connector that has poor contact, or replace harness. It is possible that temporary poor communication occurs. Delete the DTC.