KEYLESS ACCESS WITH PUSH BUTTON START SYSTEM (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)

DTC B2115 VEHICLE SPEED SENSOR ABNORMAL DETECTION

DTC DETECTING CONDITION:

The vehicle speed sensor output abnormal signals.

CAUTION:

When the power supply CM is replaced with a new unit, and the battery ground terminal is connected, it will become ignition ON. Also, if the battery is disconnected, it will resume to a condition with the battery cut off.

WIRING DIAGRAM:

STEPCHECKYESNO

1.CHECK DTC.

1) Drive for 30 seconds at approximately 30 km/h or more.

2) Read power supply CM DTCs using the Subaru Select Monitor.

Is only B2115 displayed?

Refer to the vehicle speed signal error of B2116.

2.CHECK COMBINATION METER.

Perform the self-diagnosis of combination meter.

Is the self-diagnosis of combination meter OK?

Replace the combination meter.

3.CHECK CURRENT DATA.

Using the Subaru Select Monitor, confirm the current data «Front Wheel Speed» of the body integrated unit while driving.

Does the data increase or decrease according to the driving condition?

Replace the combination meter.

4.CHECK CURRENT DATA.

Using the Subaru Select Monitor, display the current data «Vehicle Speed Signal» of the ECM while driving.

Does the data increase or decrease according to the driving condition?

Replace the combination meter.

5.CHECK CURRENT DATA.

Using the Subaru Select Monitor, confirm the ABS/VDC CM current data for «Vehicle speed signal» for the 4 individual wheels while driving.

Do the data for the 4 wheels all increase or decrease by the same figure according to the driving condition?

Check the ABS/VDC CM vehicle speed signal circuit.

6.CHECK WIRING HARNESS.

1) Disconnect the ABS/VDC CM connector.

2) Using a tester, measure the voltage between the ABS/VDC CM connector and chassis ground when the ignition switch is turned OFF and to ON.

Connector & terminal

(B310) No. 33 — Chassis ground:

Does the voltage change from less than 1 V → 8 V or more?

Check the ABS/VDC CM vehicle speed signal circuit.

7.CHECK WIRING HARNESS.

1) Disconnect the combination meter connector.

2) Using a tester, check continuity between the ABS/VDC CM connector and the combination meter.

Connector & terminal

(B310) No. 33 — (i10) No. 19:

Is there continuity?

Repair or replace the open circuit of harness.

8.CHECK COMBINATION METER.

1) Connect the ABS/VDC CM connector.

2) Using an oscilloscope, check the combination meter input signal (pulse).

Connector & terminal

(i10) No. 19 (+) — Chassis ground (−):

Does the pulse cycle become shorter as the speed increases?

Replace the combination meter.

Replace the ABS/VDC CM.