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Cadillac U2100

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

DriveUnknown. The supplied diagnostic record does not establish whether the vehicle is safe to drive with U2100.
ChargeUnknown. The supplied diagnostic record does not establish whether the vehicle is safe to charge with U2100.
ServiceService is advisable, particularly if reduced propulsion power, a service high-voltage-charging-system message, or erratic electric-power-steering boost is present. Driving and charging status are not established by the supplied evidence.
Confidence95%

Quick answer

For Cadillac vehicles in the supplied applicability data, U2100 is associated in the cited GM manufacturer communications with an inability to relearn the tire-pressure-monitoring (TPM) system. The same communications list reduced-propulsion-power and service high-voltage-charging-system messages as hybrid-specific symptoms in the broader diagnostic bulletin context. A vehicle-specific root cause is 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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DTC Cadillac U2100-00 Short ExplanationMaxidot

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1. What does U2100 mean?

For Cadillac vehicles in the supplied applicability data, U2100 is associated in the cited GM manufacturer communications with an inability to relearn the tire-pressure-monitoring (TPM) system. The same communications list reduced-propulsion-power and service high-voltage-charging-system messages as hybrid-specific symptoms in the broader diagnostic bulletin context. A vehicle-specific root cause is not established by the supplied evidence.

2. Technical explanation

The supplied diagnostic record labels U2100 as “Cannot relearn TPM.” NHTSA-hosted GM manufacturer communications 13-08-116-001, including revision I published June 29, 2023, list a Service Tire Pressure Monitoring system light and inability to relearn TPM among possible conditions. The communications also list U2100 among codes potentially associated with erratic electric-power-steering boost. For hybrids, they list “Reduced propulsion power” and “Service high voltage charging system” messages. The evidence excerpt does not establish that every U2100 occurrence causes all listed conditions, nor does it establish a specific fault for an individual vehicle.

3. What system is affected?

Tire Pressure Monitoring (TPM) system. The cited bulletin also discusses broader vehicle electrical/communication concerns and, for hybrids, high-voltage charging-system and reduced-propulsion messages; a specific affected system for an individual U2100 event is not yet established by verified evidence.

4. How serious is this code?

Unknown. The supplied diagnostic record does not provide a severity rating.

5. Symptoms you may notice

  • Service Tire Pressure Monitoring system light illuminated.
  • Cannot relearn TPM.
  • Erratic electric-power-steering boost potentially associated with U2100.
  • For hybrids: reduced propulsion power message.
  • For hybrids: service high voltage charging system message.

6. Possible causes

  • The cited GM manufacturer communications state that, after normal SI diagnostics do not identify a root cause, further checking is indicated; the supplied excerpt does not include the specific check or root cause.
  • A vehicle-specific cause for U2100 is not yet established by verified evidence.

7. Can I still drive the vehicle?

Unknown. The supplied diagnostic record does not establish whether the vehicle is safe to drive with U2100.

8. Can I charge the vehicle?

Unknown. The supplied diagnostic record does not establish whether the vehicle is safe to charge with U2100.

9. What you can safely do

  • Record all warning messages and diagnostic codes before service.
  • Arrange diagnosis using Cadillac/GM Service Information (SI) procedures.
  • Do not attempt high-voltage system repair or diagnosis yourself.

10. Step-by-step troubleshooting

  1. Perform normal diagnostics using GM Service Information, as directed by the cited manufacturer communications.
  2. If normal SI diagnostics do not identify the root cause, refer a technician to GM manufacturer communication 13-08-116-001 and its applicable revision.
  3. The exact additional inspection steps are not included in the supplied verified evidence.

11. When to contact service

Service is advisable, particularly if reduced propulsion power, a service high-voltage-charging-system message, or erratic electric-power-steering boost is present. Driving and charging status are not established by the supplied evidence.

12. What the service center may check

  • Retrieve all stored diagnostic trouble codes and vehicle warning messages.
  • Follow normal GM Service Information diagnostics.
  • Consult GM manufacturer communication 13-08-116-001, applicable revision, if no root cause is identified through normal diagnostics.

13. Possible repair or resolution

  • A specific repair is not yet established by verified evidence.
  • Repairs should follow the outcome of GM Service Information diagnostics and the applicable manufacturer communication.

14. Affected vehicles

15. Related TSBs / service bulletins

  • GM manufacturer communication 13-08-116-001I, NHTSA MC-10239102-0001, published 2023-06-29: https://static.nhtsa.gov/odi/tsbs/2023/MC-10239102-0001.pdf
  • GM manufacturer communication 13-08-116-001H, NHTSA MC-10222776-0001, published 2022-09-16: https://static.nhtsa.gov/odi/tsbs/2022/MC-10222776-0001.pdf
  • GM manufacturer communication 13-08-116-001G, NHTSA MC-10213767-9999, published 2022-01-04: https://static.nhtsa.gov/odi/tsbs/2022/MC-10213767-9999.pdf
  • GM manufacturer communication 13-08-116-001F, NHTSA MC-10183782-9999, published 2020-10-23: https://static.nhtsa.gov/odi/tsbs/2020/MC-10183782-9999.pdf
  • GM manufacturer communication 13-08-116-001E, NHTSA MC-10163272-9999, published 2019-06-26: https://static.nhtsa.gov/odi/tsbs/2019/MC-10163272-9999.pdf
  • GM manufacturer communication 13-08-116-001C, NHTSA MC-10140298-9999, published 2017-08-30: https://static.nhtsa.gov/odi/tsbs/2017/MC-10140298-9999.pdf

16. Recall information

  • No recall information was supplied or established by the verified evidence.

17. Official manufacturer information

The verified sources are NHTSA-hosted GM manufacturer communications 13-08-116-001 revisions C through I. Applicability supplied with this record is Cadillac CT6 (2014–2023), ELR (2014–2023), and LYRIQ (2014–2023), US region. Overlapping year ranges are present in the supplied data; exact applicability of a particular bulletin revision to a particular vehicle is not established by the excerpt.

19. Frequently asked questions

What does Cadillac U2100 mean?

The supplied diagnostic record defines it as “Cannot relearn TPM.”

Can U2100 be related to reduced propulsion power or a high-voltage charging message?

The cited GM communications list those as hybrid-specific conditions in the bulletin context. They do not establish that U2100 alone causes either message on every vehicle.

Can I drive or charge the vehicle?

Not yet established by verified evidence. The supplied record marks both safe-to-drive and safe-to-charge status as unknown.

What should a technician do?

The cited communications direct normal GM Service Information diagnostics first. If no root cause is found, the technician should consult the applicable version of communication 13-08-116-001; the supplied excerpt does not contain its complete procedure.

20. Sources & verification

Verified
Cadillac U2100: Cannot relearn TPM • Specific to Hybrids: – Reduced… | EV Diagnostics