DTC C1831: Insufficient Deceleration During Dynamic Parking Brake Operation

DTC detecting condition: 

This code is stored when deceleration speed is lower than normal while dynamic parking is operating.

Trouble symptom: 

Dynamic parking through the hydraulic control (VDC H/U pressure) does not operate.

1. CHECK DTC. 
   1. Using the Subaru Select Monitor, perform the clear memory. Ref. to COMMON (diag)>CLEAR MEMORY .
   2. Execute the inspection mode. Ref. to BRAKE CONTROL (DIAGNOSTICS)>INSPECTION MODE .
   3. Perform the dynamic parking.
   4. Read the DTC using Subaru Select Monitor. Ref. to BRAKE CONTROL (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

   Is DTC C1831 a current malfunction?

   Yes  : Go to  2.

   No  : It results from a temporary braking force change.

2. CHECK BRAKE SYSTEM. 
   1. Turn the ignition switch to OFF.
   2. Start the engine.
   3. Perform ABS operation check. Ref. to VEHICLE DYNAMICS CONTROL (VDC)>VDC CONTROL MODULE AND HYDRAULIC CONTROL UNIT (VDCCM & H/U)>INSPECTION>CHECKING THE HYDRAULIC UNIT ABS OPERATION WITH THE BRAKE TESTER .

   Is the measured value within the standard value?

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

   No  : Check the brake system.