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Subaru B2256

Verify signal strength ≥23%. If ~0%, move the vehicle

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceService need is not established by the supplied verified evidence. A Subaru service provider can apply the manufacturer diagnostic procedure if further diagnosis is needed.
Confidence95%

Quick answer

For Subaru DTC B2256, verified evidence identifies a problem between the Data Communication Module (DCM) and the infotainment unit. The cited Subaru service procedure says to verify signal strength is at least 23%; if it is approximately 0%, move the vehicle.

This page separates verified manufacturer/regulator evidence from supporting material. Unsupported causes, repairs or safety conclusions are not guessed.

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1. What does B2256 mean?

For Subaru DTC B2256, verified evidence identifies a problem between the Data Communication Module (DCM) and the infotainment unit. The cited Subaru service procedure says to verify signal strength is at least 23%; if it is approximately 0%, move the vehicle.

2. Technical explanation

B2256 is referenced in Subaru manufacturer communications as a telematics DTC that can indicate a problem between the DCM and the infotainment unit. The official procedure also notes that current telematics DTCs can affect test results by delaying DCM power-down. For a zero-signal condition, the documented check is signal strength: verify at least 23%. If signal strength is approximately 0%, move the vehicle.

3. What system is affected?

Telematics: Data Communication Module (DCM) and infotainment-unit communication.

4. How serious is this code?

Unknown. Verified evidence does not assign a severity level.

5. Symptoms you may notice

  • A telematics DTC B2256 may be present.
  • A low or approximately zero signal-strength reading may be relevant to the documented diagnostic procedure.

6. Possible causes

  • A problem between the DCM and the infotainment unit.
  • Signal strength of approximately 0% is addressed by moving the vehicle.

7. Can I still drive the vehicle?

Not yet established by verified evidence.

8. Can I charge the vehicle?

Not yet established by verified evidence.

9. What you can safely do

  • Verify the vehicle's signal strength is at least 23%.
  • If signal strength is approximately 0%, move the vehicle.
  • Have current telematics DTCs considered during diagnosis because they can delay DCM power-down and skew results.

10. Step-by-step troubleshooting

  1. Check whether current telematics DTCs are present.
  2. Verify signal strength is at least 23%.
  3. If the reading is approximately 0%, move the vehicle and reassess signal strength.

11. When to contact service

Service need is not established by the supplied verified evidence. A Subaru service provider can apply the manufacturer diagnostic procedure if further diagnosis is needed.

12. What the service center may check

  • Check for current telematics DTCs that may affect results by delaying DCM power-down.
  • Consider B2256 as indicating a possible issue between the DCM and infotainment unit.
  • Verify signal strength is at least 23%.
  • For a reading near 0%, move the vehicle.

13. Possible repair or resolution

  • Not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Subaru manufacturer communication 15-308-23R, published through NHTSA as MC-11036807-0001 on 2026-08-20: identifies B2256 as a DTC that can indicate a problem between the DCM and infotainment unit; instructs verification of signal strength at or above 23%, and moving the vehicle if signal strength is approximately 0%.
  • Subaru manufacturer communication 15-308-23R, published through NHTSA as MC-11024869-0001 on 2025-10-28: contains the same documented guidance.

16. Recall information

  • No recall information was supplied in the verified evidence.

17. Official manufacturer information

Official NHTSA-hosted Subaru manufacturer communications: https://static.nhtsa.gov/odi/tsbs/2026/MC-11036807-0001.pdf and https://static.nhtsa.gov/odi/tsbs/2025/MC-11024869-0001.pdf. Supplied applicability records list US-market Subaru Crosstrek (2019–2026), Solterra (2019–2026), Trailseeker (2019–2026), and Uncharted (2019–2026); overlapping records also list Crosstrek and Solterra through 2025.

19. Frequently asked questions

What does Subaru B2256 mean?

Verified evidence says B2256 can indicate a problem between the Data Communication Module (DCM) and the infotainment unit.

What signal strength should be verified for B2256?

The cited Subaru procedure says to verify signal strength is at least 23%.

What if signal strength is near 0%?

The cited procedure says to move the vehicle if signal strength is approximately 0%.

Can I drive or charge with B2256?

Not yet established by verified evidence.

20. Sources & verification

Verified
Subaru B2256: Verify signal strength ≥23%. If ~0%, move the vehicle | EV Diagnostics