DTC B227B: Push Engine Start Switch Input Performance

DTC detecting condition: 

When any of the following conditions is established.

• Judgment of Switch ON stuck is present. (When any of the following conditions is established.)
  1. When the status continues for 40 seconds where push button ignition switch input (SSW1 terminal) is ON ("L" level) and push button ignition switch input (SSW2 terminal) is OFF ("H" level).
  2. When the status continues for 40 seconds where push button ignition switch input (SSW1 terminal) is OFF ("H" level) and push button ignition switch input (SSW2 terminal) is ON ("L" level).
• Judgment of OFF stuck is present. (When any of the following conditions is established 10 consecutive times.)

  Only when a series of judgment is continuously made with the same judgment condition under either condition of 1 or 2.

  1. Push button ignition switch input (SSW1 terminal) is OFF ("H" level) → ON ("L" level) → OFF, and push button ignition switch input (SSW2 terminal) is OFF ("H" level).
  2. Push button ignition switch input (SSW1 terminal) is OFF ("H" level), and push button ignition switch input (SSW2 terminal) is OFF ("H" level) → ON ("L" level) → OFF.

Trouble symptom: 

• Power supply cannot be turned ON.
• Power supply cannot be turned OFF.

Wiring diagram: 

Keyless access with push button start system Ref. to WIRING SYSTEM>KEYLESS ACCESS WITH PUSH BUTTON START SYSTEM>WIRING DIAGRAM .

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK DTC  .
   1. Turn the ignition switch to ON.
   2. Using the Subaru Select Monitor, perform the clear memory of [Keyless Access with Push Button Start (Power Supply)]. Ref. to COMMON (DIAGNOSTICS)>CLEAR MEMORY .
   3. Press the push button ignition switch to perform OFF → ACC ON → IGN ON respectively for one minute.
   4. Turn the ignition switch to OFF.
   5. Disconnect the connector from the keyless access control module and reconnect it.
   6. Turn the ignition switch to ON.
   7. Read the DTC of [Keyless Access with Push Button Start (Power Supply)] using the Subaru Select Monitor. Ref. to KEYLESS ACCESS WITH PUSH BUTTON START (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

   Is DTC B227B displayed? (Current code)

   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 HARNESS (OPEN CIRCUIT)  .
   1. Turn the ignition switch to OFF.
   2. Disconnect the push button ignition switch connector.
   3. Disconnect the keyless access control module connector.
   4. Using a tester, measure the resistance between the push button ignition switch connector and the keyless access control module connector and between the push button ignition switch connector and chassis ground.

      Connector & terminal 

      (i150) No. 2 - (i75) No. 9:

      (i150) No. 7 - (i75) No. 8:

      (i150) No. 5 - Chassis ground:

   Is the resistance less than 1 Ω?

   Yes:  Go to  3.

   No:  Repair or replace the open circuit of harness.

3. CHECK PUSH BUTTON IGNITION SWITCH UNIT  .

   Perform individual inspection of the push button ignition switch. Ref. to SECURITY AND LOCKS>PUSH BUTTON IGNITION SWITCH .

   Is the check result OK?

   Yes:  Go to  4.

   No:  Replace the push button ignition switch. Ref. to SECURITY AND LOCKS>PUSH BUTTON IGNITION SWITCH .

4. CHECK DATA MONITOR  .
   1. Connect the disconnected connectors.
   2. Turn the ignition switch to ON.
   3. Using the Subaru Select Monitor, check the following items in the [Data Monitor] of [Keyless Access with Push Button Start (Power Supply)]. Ref. to KEYLESS ACCESS WITH PUSH BUTTON START (DIAGNOSTICS)>DATA MONITOR .
   • Push start SW 1
   • Push start SW 2

   Is it turned [ON] when pressing the push button ignition switch?

   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:  Replace the keyless access control module. Ref. to SECURITY AND LOCKS>KEYLESS ACCESS CONTROL MODULE .