DTC C1422: VDC Interruption For Engine Convenience

DTC detecting condition: 

A fault is detected if engine control prohibition flag from ECM is received.

Trouble symptom: 

• VDC does not operate.
• Hill start assist does not operate.
  CAUTION: Before performing diagnosis, refer to "CAUTION" in "General Description". Ref. to BRAKE CONTROL (DIAGNOSTICS)>GENERAL DESCRIPTION>CAUTION .
  NOTE: The warning light goes off if the engine control prohibition flag from ECM returns normally.

1. CHECK COOPERATION CONTROL FEASIBILITY OF ECM USING SUBARU SELECT MONITOR  .
   1. Start the engine, and run the engine at idle approximately 5 minutes.
   2. Using the Subaru Select Monitor, read data of [E/G Torque Down Control Stop Flag] in the [Data Monitor] of [Brake Control]. Ref. to BRAKE CONTROL (DIAGNOSTICS)>DATA MONITOR .

   Is the [E/G Torque Down Control Stop Flag] set to "[1]"?

   Yes  : Go to  4.

   No  : Go to  2.

2. CHECK WARNING LIGHT  .

   Check whether the VDC warning light illuminates after driving for 1 minute or more at a speed of 10 km/h (6 MPH) or more.

   Does the VDC warning light illuminate?

   Yes  : Go to  3.

   No  : VDC is normal. Using the Subaru Select Monitor, perform the clear memory of [Brake Control]. Ref. to COMMON (DIAG)>CLEAR MEMORY .

   NOTE: DTC may be recorded if cranking is performed during driving.
3. CHECK POOR CONTACT OF CONNECTORS  .

   Is there poor contact of ECM connector?

   Yes  : Repair the connector.

   No  : Go to  4.

4. CHECK DTC OF ECM  .

   Read the DTC of [Engine] using the Subaru Select Monitor. Ref. to ENGINE (DIAGNOSTICS) (H4DO) (EXCEPT FOR HEV)>DIAGNOSTIC TROUBLE CODE (DTC) .

   Are any DTCs displayed?

   Yes  : Perform the diagnosis according to the DTC. Ref. to ENGINE (DIAGNOSTICS) (H4DO) (EXCEPT FOR HEV)>DIAGNOSTIC TROUBLE CODE (DTC)>LIST .

   No  : Go to  5.

5. CHECK VDC Control Module & H/U  .
   1. Connect all connectors.
   2. Using the Subaru Select Monitor, perform the clear memory of [Brake Control]. Ref. to COMMON (DIAG)>CLEAR MEMORY .
   3. Execute the inspection mode. Ref. to BRAKE CONTROL (DIAGNOSTICS)>INSPECTION MODE .
   4. Read the DTC of [Brake Control] using the Subaru Select Monitor. Ref. to BRAKE CONTROL (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

   Is the same DTC displayed?

   Yes  : Replace the VDC Control Module & H/U. Ref. to VEHICLE DYNAMICS CONTROL (VDC)>VDC CONTROL MODULE AND HYDRAULIC CONTROL UNIT (VDC Control Module & H/U) .

   No  : Go to  6.

6. CHECK DETECTION OF OTHER DTCS FOR VDC  .

   Read the DTC of [Brake Control] using the Subaru Select Monitor. Ref. to BRAKE CONTROL (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

   Is any other DTC displayed?

   Yes  : Perform the diagnosis according to the DTC. Ref. to BRAKE CONTROL (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)>LIST .

   No  : Currently, it is normal. There may have been a temporary poor contact in the harness and connector or a temporary noise interference.