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Cadillac U1624

to-Bumper cov

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceService need is not established by the supplied diagnostic record. However, GM manufacturer communications provide technician guidance for this code on applicable Cadillac LYRIQ vehicles; contact an authorized Cadillac/GM service facility for evaluation.
Confidence95%

Quick answer

For certain US-market 2023 and 2025 Cadillac LYRIQ vehicles, DTC U1624 symptom 00 is identified in GM/NHTSA manufacturer communications as a code that may be found in the K124 Image Processing Module (IPCM) or in recent history. The supplied evidence does not establish a plain-language definition beyond the database title “to-Bumper cov.”

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 U1624 mean?

For certain US-market 2023 and 2025 Cadillac LYRIQ vehicles, DTC U1624 symptom 00 is identified in GM/NHTSA manufacturer communications as a code that may be found in the K124 Image Processing Module (IPCM) or in recent history. The supplied evidence does not establish a plain-language definition beyond the database title “to-Bumper cov.”

2. Technical explanation

GM bulletin 25-NA-060 states that technicians may find U1624 symptom 00, along with U053C symptom 00 and U023B symptom 00, set in the K124 Image Processing Module (IPCM) or in recent history. Earlier GM communications PIC6500A and PIC6500B also list U1624 symptom 00 among covered DTCs. The verified evidence does not establish the underlying failure mechanism or a consumer-facing meaning for U1624.

3. What system is affected?

K124 Image Processing Module (IPCM), based on GM bulletin 25-NA-060.

4. How serious is this code?

Unknown. The supplied verified evidence does not assign a severity level.

5. Symptoms you may notice

  • A U1624 symptom 00 DTC may be stored in the K124 Image Processing Module (IPCM) or may appear in recent history.
  • No driver-visible symptoms are established by the supplied verified evidence.

6. Possible causes

  • Not yet established by verified evidence. PIC6500A states that engineering was aware of an issue and working on a resolution, but the supplied evidence does not specify a technical root cause.

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

  • Arrange diagnosis with an authorized Cadillac/GM service facility if U1624 is present or if there is a related customer concern.
  • Provide the technician with the stored DTC details, including symptom byte 00 if available.
  • Do not replace the controller solely because U1624 symptom 00 is present under the conditions covered by PIC6500A; that communication specifically instructed dealers not to replace the controller for listed codes while awaiting an engineering resolution.

10. Step-by-step troubleshooting

  1. A qualified technician can confirm whether U1624 symptom 00 is current or stored in recent history and whether it is in the K124 IPCM.
  2. For vehicles and conditions covered by GM communications, technicians should consult the applicable current GM service information and bulletin guidance.
  3. PIC6500A states that if none of its listed DTCs are setting, normal SI diagnostics should be followed.

11. When to contact service

Service need is not established by the supplied diagnostic record. However, GM manufacturer communications provide technician guidance for this code on applicable Cadillac LYRIQ vehicles; contact an authorized Cadillac/GM service facility for evaluation.

12. What the service center may check

  • Check for U1624 symptom 00 in the K124 Image Processing Module (IPCM) and in recent history, as described in bulletin 25-NA-060.
  • Review applicable GM communications 25-NA-060, PIC6500B, and PIC6500A.
  • Verify the customer concern, as instructed in PIC6500A.
  • If the listed DTC conditions are not present, follow normal GM Service Information diagnostics, as stated in PIC6500A.

13. Possible repair or resolution

  • PIC6500A instructed dealers to verify the customer concern and wait until engineering provided a resolution.
  • PIC6500A instructed dealers not to replace the controller when one of its listed DTCs, including U1624 symptom 00, was set.
  • The supplied evidence does not establish the final repair procedure or whether bulletin 25-NA-060 provides a repair resolution.

14. Affected vehicles

15. Related TSBs / service bulletins

  • GM/Cadillac bulletin 25-NA-060, published March 11, 2025: identifies U1624 symptom 00 among DTCs that may be found in the K124 IPCM or recent history. NHTSA manufacturer communication 11017004.
  • GM/Cadillac PIC6500B, published September 11, 2024: lists U1624 symptom 00 among DTCs addressed by the communication. NHTSA manufacturer communication 11007683.
  • GM/Cadillac PIC6500A, published May 24, 2023: lists U1624 symptom 00, instructs dealers not to replace the controller for listed DTCs, and states engineering was working on a resolution. NHTSA manufacturer communication 10237683.

16. Recall information

  • No recall is established by the supplied verified evidence.

17. Official manufacturer information

Official NHTSA-hosted GM manufacturer communications: 25-NA-060: https://static.nhtsa.gov/odi/tsbs/2025/MC-11017004-0001.pdf ; PIC6500B: https://static.nhtsa.gov/odi/tsbs/2024/MC-11007683-0001.pdf ; PIC6500A: https://static.nhtsa.gov/odi/tsbs/2023/MC-10237683-9999.pdf

19. Frequently asked questions

What does Cadillac U1624 mean?

The supplied database labels the code “to-Bumper cov,” but the verified manufacturer communications do not provide a clearer plain-language definition. They identify U1624 symptom 00 as a DTC that may be present in the K124 Image Processing Module or in recent history.

Which vehicles are covered by the supplied applicability evidence?

The supplied applicability evidence identifies US-market Cadillac LYRIQ vehicles for model years 2023 and 2025.

Should the IPCM/controller be replaced for U1624?

PIC6500A specifically instructed dealers not to replace the controller when a listed DTC, including U1624 symptom 00, was set. The supplied evidence does not establish a later final repair procedure.

Is U1624 a recall?

No recall is established by the supplied verified evidence.

20. Sources & verification

Verified
Cadillac U1624: to-Bumper cov | EV Diagnostics