DTC B2C05: Sonar Control Module Power Supply

Outline of diagnosis: 

Voltage supply to the ignition power supply terminal was 16 V or more.

Time needed for diagnosis: 

5000 ms

Recovery conditions: 

Ignition switch OFF - ON

Wiring diagram: 

Reverse Automatic Braking Ref. to WIRING SYSTEM>REVERSE ASSIST BRAKING SYSTEM .

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK CONNECTOR  .
   1. Turn the ignition switch to OFF.
   2. Disconnect the RAB control module connector (L81).
   3. Connect the disconnected connectors.
   4. Turn the ignition switch to ON.
   5. Read the DTC of [Reverse Assist Braking] using the Subaru Select Monitor. Ref. to REVERSE AUTOMATIC BRAKING (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

   Is DTC B2C05 displayed? (Current malfunction)

   Yes  : Go to  2 .

   No  : Even if DTC is displayed, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

   NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
2. CHECK RAB CONTROL MODULE POWER SUPPLY CIRCUIT  .
   1. Turn the ignition switch to OFF.
   2. Disconnect the RAB control module connector (L81).
   3. Turn the ignition switch to ON.
   4. Using a tester, measure the voltage between the RAB control module connector (L81) and chassis ground.

   Connector and terminal 

   (L81) No. 14 (+) - Chassis ground (-):

   Is the voltage 16 V or less?

   Yes  : Replace the RAB control module. Ref. to REVERSE AUTOMATIC BRAKING>REVERSE ASSIST BRAKING CONTROL MODULE .

   No  : Check the harness between the RAB control module connector (L81) and power supply.