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Cadillac U3637

U3620, U3622, U3624, U3626, U3628

DriveUnknown. The supplied diagnostic record lists safe-to-drive status as unknown.
ChargeUnknown. The supplied diagnostic record lists safe-to-charge status as unknown.
ServiceService involvement is not explicitly established by the supplied record, which lists service-required status as unknown. However, professional diagnosis is appropriate because the evidence does not define U3637 or provide a safe repair path.
Confidence95%

Quick answer

For 2023–2024 Cadillac LYRIQ vehicles in the US, U3637 appears in an official GM communication history for PIE0788, but the June 10, 2024 revision removed U3637 from the listed DTCs. The supplied evidence does not establish the code’s definition, vehicle symptoms, driving or charging status, cause, or repair.

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 U3637 mean?

For 2023–2024 Cadillac LYRIQ vehicles in the US, U3637 appears in an official GM communication history for PIE0788, but the June 10, 2024 revision removed U3637 from the listed DTCs. The supplied evidence does not establish the code’s definition, vehicle symptoms, driving or charging status, cause, or repair.

2. Technical explanation

The diagnostic record labels U3637 with the canonical text “U3620, U3622, U3624, U3626, U3628.” This supplied data does not provide a technical definition of U3637 or identify the module/system involved. NHTSA-hosted manufacturer communication PIE0788B states that the June 10, 2024 revision removed U3637, along with multiple other DTCs, from the communication’s listed DTCs. PIE0788C repeats that revision history. Therefore, U3637 should not be treated as an active listed keyword/DTC within the revised PIE0788 material based on the provided evidence.

3. What system is affected?

Not yet established by verified evidence.

4. How serious is this code?

Unknown. The supplied diagnostic record lists severity as unknown.

5. Symptoms you may notice

  • Not yet established by verified evidence.

6. Possible causes

  • Not yet established by verified evidence.

7. Can I still drive the vehicle?

Unknown. The supplied diagnostic record lists safe-to-drive status as unknown.

8. Can I charge the vehicle?

Unknown. The supplied diagnostic record lists safe-to-charge status as unknown.

9. What you can safely do

  • Use the vehicle information and warning messages shown by the vehicle as the immediate operating reference.
  • Arrange diagnosis by a Cadillac dealer or qualified service provider if U3637 is present or returns.
  • Do not attempt high-voltage-system diagnosis or repair based on this information.

10. Step-by-step troubleshooting

  1. Record the complete diagnostic scan result, including any accompanying DTCs and whether U3637 is current or history.
  2. Provide the VIN, model year, software/module scan report, and any vehicle messages to the servicing facility.
  3. Verify the current applicable Cadillac service information using the vehicle VIN. The supplied evidence does not provide a repair procedure for U3637.

11. When to contact service

Service involvement is not explicitly established by the supplied record, which lists service-required status as unknown. However, professional diagnosis is appropriate because the evidence does not define U3637 or provide a safe repair path.

12. What the service center may check

  • Confirm whether the vehicle is a 2023–2024 Cadillac LYRIQ for the US market.
  • Confirm the exact DTC and all accompanying DTCs with an appropriate scan tool.
  • Check current Cadillac service information applicable to the VIN.
  • Review PIE0788 revision status: the supplied evidence says U3637 was removed from the DTC list in the June 10, 2024 revision.

13. Possible repair or resolution

  • Not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • NHTSA Manufacturer Communication PDF 11004345, PIE0788B, published June 10, 2024: its evidence summary states that U3637 was removed from the listed DTCs in that revision.
  • NHTSA Manufacturer Communication PDF 11004943, PIE0788C, published June 28, 2024: its evidence summary repeats the June 10, 2024 revision history removing U3637 from the listed DTCs.

16. Recall information

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

17. Official manufacturer information

Official NHTSA-hosted manufacturer communications supplied: PIE0788B (https://static.nhtsa.gov/odi/tsbs/2024/MC-11004345-0001.pdf) and PIE0788C (https://static.nhtsa.gov/odi/tsbs/2024/MC-11004943-0001.pdf). Both supplied summaries indicate that U3637 was removed from the communication’s DTC list in the June 10, 2024 revision.

19. Frequently asked questions

What does Cadillac DTC U3637 mean?

Not yet established by verified evidence. The supplied record does not provide a code definition or affected system.

Does PIE0788 apply to U3637?

The supplied evidence shows U3637 was removed from the listed DTCs in the June 10, 2024 revision of PIE0788. It does not establish a current PIE0788 diagnostic or repair procedure for U3637.

Which vehicles are covered by the supplied applicability data?

The supplied applicability data identifies US-market 2023–2024 Cadillac LYRIQ vehicles.

Is it safe to drive or charge with U3637?

Not yet established by verified evidence. Both safe-to-drive and safe-to-charge fields are listed as unknown.

20. Sources & verification

Verified
Cadillac U3637: U3620, U3622, U3624, U3626, U3628 | EV Diagnostics