DTC B228A: Engine Speed Signal(With Auto Start Stop)

DTC detecting condition: 

For model with Auto Start Stop, when any of the following conditions continues for 20 seconds with ignition switch ON.

• Engine speed signal on direct line is less than 200 rpm, and engine speed signal on CAN is 1000 rpm or more.
• Engine speed signal on direct line is 1000 rpm or more, and engine speed signal on CAN is less than 200 rpm.

Wiring diagram: 

Keyless access with push button start system Refer to WIRING SYSTEM>Keyless Access With Push Button Start System>WIRING DIAGRAM .

• FB engine model

Courtesy of SUBARU OF AMERICA, INC.

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK LAN SYSTEM  .

   Perform the diagnosis for LAN system. Refer to LAN SYSTEM (DIAGNOSTICS)>Basic Diagnostic Procedure>PROCEDURE .

   Is the check result OK?

   Yes:  Go to  2.

   No  : Perform the inspection according to the diagnosis for LAN system.

2. CHECK COMBINATION METER  .

   Confirm that the speedometer is displayed normally.

   Is combination meter display OK?

   Yes:  Go to  3.

   No  : Perform the diagnosis for the engine. Refer to ENGINE (DIAGNOSTICS) (H4DO)>Basic Diagnostic Procedure>PROCEDURE . Refer to ENGINE (DIAGNOSTICS) (H4DOTC)>Basic Diagnostic Procedure>PROCEDURE .

3. CHECK DATA MONITOR  .

   Using the Subaru Select Monitor, check the following items in the [Data Monitor] of [Keyless Access with Push Button Start(Power Supply)]. Refer to KEYLESS ACCESS WITH PUSH BUTTON START SYSTEM (DIAGNOSTICS)>DATA MONITOR .

   • Engine Speed

   Can the data be read normally?

   Yes:  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.

   No  : Go to  4.

4. CHECK HARNESS (OPEN CIRCUIT)  .
   1. Disconnect the keyless access Control Module connector.
   2. Disconnect the EControl Module connector.
   3. Using a tester, measure the resistance between the keyless access Control Module connector and EControl Module connector.

   Connector & terminal 

   FB engine model 

   (i91) No. 6 - (B62) No. 21:

   FA engine model 

   (i91) No. 6 - (B61) No. 24:

   Is the resistance less than 1 Ω?

   Yes:  Go to  5.

   No  : Repair or replace the open circuit of harness.

5. CHECK HARNESS (GROUND SHORT CIRCUIT)  .

   Using a tester, measure the resistance between the keyless access Control Module connector and chassis ground.

   Connector & terminal 

   (i91) No. 6 - Chassis ground:

   Is the resistance 10 kΩ or more?

   Yes:  Go to  6.

   No  : Repair or replace the short circuit of the harness.

6. CHECK HARNESS  .
   1. Connect the keyless access Control Module connector and EControl Module connector.
   2. Using an oscilloscope, measure the waveform between the keyless access Control Module connector and chassis ground.

   Connector & terminal 

   (i91) No. 6 - Chassis ground:

   Does the pulse stop when the engine is stopped, and does the pulse generate when the engine is started?

   Yes:  Replace the keyless access Control Module. Refer to SECURITY AND LOCKS>KEYLESS ACCESS Control Module .

   No  : Perform the diagnosis for the engine. Refer to ENGINE (DIAGNOSTICS) (H4DO)>Basic Diagnostic Procedure>PROCEDURE . Refer to ENGINE (DIAGNOSTICS) (H4DOTC)>Basic Diagnostic Procedure>PROCEDURE .