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Chevrolet U2109

Cannot relearn TPM • Specific to Hybrids: – Reduced propulsion power message. – Service high voltage charging system message. Cause If nothing else can be identified as the root ca

DriveNot yet established by verified evidence. The supplied diagnostic record lists safe-to-drive status as unknown. Because the official bulletin summary associates U2109 with potentially erratic electric power-steering boost, obtain professional evaluation if that condition is present.
ChargeNot yet established by verified evidence. The supplied diagnostic record lists safe-to-charge status as unknown. For hybrids displaying a Service High Voltage Charging System message, the supplied evidence does not establish charging guidance.
ServiceProfessional diagnosis is appropriate because the supplied evidence does not establish a single cause or owner-level repair. Promptly seek service if electric power-steering behavior is erratic or if hybrid propulsion-power or high-voltage-charging-system messages are displayed.
Confidence95%

Quick answer

For Chevrolet vehicles listed in the verified applicability data, U2109 is identified as “Cannot relearn TPM.” An official GM/NHTSA service bulletin also associates U2109 with potentially erratic electric power-steering boost and, for hybrids, reduced-propulsion-power and service-high-voltage-charging-system messages. The root cause and appropriate repair are not established by the supplied evidence.

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 U2109 mean?

For Chevrolet vehicles listed in the verified applicability data, U2109 is identified as “Cannot relearn TPM.” An official GM/NHTSA service bulletin also associates U2109 with potentially erratic electric power-steering boost and, for hybrids, reduced-propulsion-power and service-high-voltage-charging-system messages. The root cause and appropriate repair are not established by the supplied evidence.

2. Technical explanation

The supplied diagnostic record defines U2109 as “Cannot relearn TPM.” The available official manufacturer communications are bulletin 13-08-116-001, in multiple revisions. Their summaries list a Service Tire Pressure Monitoring (TPM) system light with inability to relearn TPM. They also state that erratic electric power-steering boost may be associated with U2109, U2107, U2100, B1325, and C0000. For hybrids, the summaries list reduced propulsion power and a Service High Voltage Charging System message. The supplied excerpts do not establish that every U2109 event has these symptoms, nor do they establish a specific component failure or repair.

3. What system is affected?

Tire Pressure Monitoring (TPM) system is directly identified by the diagnostic meaning. The verified bulletin summary also associates U2109 with electric power-steering behavior; hybrid-specific messages involving propulsion power and the high-voltage charging system are listed in the bulletin summary.

4. How serious is this code?

Not yet established by verified evidence. The diagnostic record lists severity as unknown.

5. Symptoms you may notice

  • Service Tire Pressure Monitoring (TPM) system light illuminated and inability to relearn TPM are identified in the official bulletin summary.
  • Erratic electric power-steering boost may be associated with U2109 according to the official bulletin summary.
  • For hybrids, a Reduced Propulsion Power message is listed in the official bulletin summary.
  • For hybrids, a Service High Voltage Charging System message is listed in the official bulletin summary.

6. Possible causes

  • The supplied official bulletin summary says that normal diagnostics should be used to identify the root cause, but the supplied evidence does not provide the complete cause statement or identify a specific root cause for U2109.
  • Not yet established by verified evidence.

7. Can I still drive the vehicle?

Not yet established by verified evidence. The supplied diagnostic record lists safe-to-drive status as unknown. Because the official bulletin summary associates U2109 with potentially erratic electric power-steering boost, obtain professional evaluation if that condition is present.

8. Can I charge the vehicle?

Not yet established by verified evidence. The supplied diagnostic record lists safe-to-charge status as unknown. For hybrids displaying a Service High Voltage Charging System message, the supplied evidence does not establish charging guidance.

9. What you can safely do

  • Record all displayed warnings and any diagnostic trouble codes before service.
  • Arrange professional diagnosis using normal manufacturer diagnostic procedures.
  • Do not attempt high-voltage system repair or diagnosis yourself.

10. Step-by-step troubleshooting

  1. Have a qualified service facility perform normal diagnostics to identify the root cause, as referenced by the official bulletin summary.
  2. Verify whether the TPM relearn can be completed and whether the TPM warning is illuminated.
  3. Document whether erratic electric power-steering boost, Reduced Propulsion Power, or Service High Voltage Charging System messages are present.

11. When to contact service

Professional diagnosis is appropriate because the supplied evidence does not establish a single cause or owner-level repair. Promptly seek service if electric power-steering behavior is erratic or if hybrid propulsion-power or high-voltage-charging-system messages are displayed.

12. What the service center may check

  • Perform normal manufacturer diagnostic procedures to identify the root cause.
  • Assess the TPM warning and inability to complete TPM relearn.
  • Assess for potentially associated electric power-steering concerns.
  • For hybrids, assess any Reduced Propulsion Power or Service High Voltage Charging System message.

13. Possible repair or resolution

  • Not yet established by verified evidence. The supplied records do not provide a verified repair procedure or confirmed resolution for U2109.

14. Affected vehicles

15. Related TSBs / service bulletins

  • GM bulletin 13-08-116-001I, NHTSA manufacturer communication MC-10239102-0001, published June 29, 2023: https://static.nhtsa.gov/odi/tsbs/2023/MC-10239102-0001.pdf
  • GM bulletin 13-08-116-001H, NHTSA manufacturer communication MC-10222776-0001, published September 16, 2022: https://static.nhtsa.gov/odi/tsbs/2022/MC-10222776-0001.pdf
  • GM bulletin 13-08-116-001G, NHTSA manufacturer communication MC-10213767-9999, published January 4, 2022: https://static.nhtsa.gov/odi/tsbs/2022/MC-10213767-9999.pdf
  • GM bulletin 13-08-116-001F, NHTSA manufacturer communication MC-10183782-9999, published October 23, 2020: https://static.nhtsa.gov/odi/tsbs/2020/MC-10183782-9999.pdf
  • GM bulletin 13-08-116-001E, NHTSA manufacturer communication MC-10163272-9999, published June 26, 2019: https://static.nhtsa.gov/odi/tsbs/2019/MC-10163272-9999.pdf
  • GM bulletin 13-08-116-001C, NHTSA manufacturer communication MC-10140298-9999, published August 30, 2017: https://static.nhtsa.gov/odi/tsbs/2017/MC-10140298-9999.pdf

16. Recall information

  • Not yet established by verified evidence. No recall information was supplied.

17. Official manufacturer information

The supplied official evidence consists of NHTSA-hosted GM manufacturer communications for bulletin 13-08-116-001 and revisions. Verified applicability data lists Chevrolet Blazer, Bolt EV, Bolt EUV, Equinox, Spark, and Volt entries in the US across overlapping year ranges from 2011 through 2024. Exact vehicle applicability should be confirmed against the vehicle VIN and the complete bulletin.

19. Frequently asked questions

What does Chevrolet U2109 mean?

The supplied diagnostic record identifies U2109 as “Cannot relearn TPM.”

Can U2109 be related to power steering?

The official bulletin summary states that erratic electric power-steering boost may be associated with U2109.

Can U2109 occur with hybrid warnings?

The official bulletin summary lists Reduced Propulsion Power and Service High Voltage Charging System messages as hybrid-specific items. It does not establish that they occur with every U2109 event.

Is it safe to drive or charge with U2109?

Not yet established by verified evidence. Both safe-to-drive and safe-to-charge status are recorded as unknown in the supplied diagnostic data.

What repair fixes U2109?

Not yet established by verified evidence. The supplied official summary directs use of normal diagnostics to identify the root cause but does not provide a verified repair in the supplied material.

20. Sources & verification

Verified
Chevrolet U2109: Cannot relearn TPM • Specific to Hybrids: – Reduced… | EV Diagnostics