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Cadillac P07A7

3 clutch return spring ring (1) that has come out of its groove, causing the Variable 1-4 and 1-3 Clutch Piston Return Spring Plate to contact (2) the variable clutch plate assembl

DriveNot yet established by verified evidence. The bulletin does document that limited vehicle speed may occur.
ChargeNot yet established by verified evidence.
ServiceContact a Cadillac/GM service facility for diagnosis, particularly if the MIL is illuminated or vehicle speed is limited.
Confidence95%

Quick answer

For applicable 2017–2018 Cadillac CT6 vehicles, DTC P07A7 is documented in GM bulletin 19NA128 as “Transmission Clutch 3 Stuck On.” The bulletin describes a possible internal transmission/hybrid drive cause involving a 1-3 clutch return spring ring out of its groove.

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 P07A7 mean?

For applicable 2017–2018 Cadillac CT6 vehicles, DTC P07A7 is documented in GM bulletin 19NA128 as “Transmission Clutch 3 Stuck On.” The bulletin describes a possible internal transmission/hybrid drive cause involving a 1-3 clutch return spring ring out of its groove.

2. Technical explanation

GM bulletin 19NA128 states that a 1-3 clutch return spring ring may come out of its groove. This can allow the Variable 1-4 and 1-3 Clutch Piston Return Spring Plate to contact the variable clutch plate assembly. The bulletin associates this condition with P07A7 stored in the Hybrid Powertrain Control Module (HPCM).

3. What system is affected?

Hybrid Powertrain Control Module (HPCM) and the transmission/hybrid drive clutch assembly.

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

  • Malfunction Indicator Lamp (MIL) illuminated.
  • Limited vehicle speed.

6. Possible causes

  • GM bulletin 19NA128 identifies a possible 1-3 clutch return spring ring that has come out of its groove.
  • The displaced ring can cause the Variable 1-4 and 1-3 Clutch Piston Return Spring Plate to contact the variable clutch plate assembly.

7. Can I still drive the vehicle?

Not yet established by verified evidence. The bulletin does document that limited vehicle speed may occur.

8. Can I charge the vehicle?

Not yet established by verified evidence.

9. What you can safely do

  • Arrange diagnosis by a qualified Cadillac/GM service facility.
  • Provide the technician with DTC P07A7 and reference GM bulletin 19NA128.
  • Do not attempt internal transmission or hybrid-drive disassembly.

10. Step-by-step troubleshooting

  1. A technician may confirm whether P07A7 is set in the Hybrid Powertrain Control Module (HPCM).
  2. GM bulletin 19NA128 should be reviewed for applicable diagnostic and service information.

11. When to contact service

Contact a Cadillac/GM service facility for diagnosis, particularly if the MIL is illuminated or vehicle speed is limited.

12. What the service center may check

  • Confirm vehicle applicability: Cadillac CT6, model years 2017–2018, with 2.0L LTG and Automatic-Hybrid Electric (MRD).
  • Confirm RPO HP9: Electrified Propulsion-Electric, PHEV, Gen 2, RWD.
  • Check the HPCM for DTC P07A7.
  • Review GM bulletin 19NA128.

13. Possible repair or resolution

  • Not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • GM bulletin 19NA128, published December 16, 2020; NHTSA manufacturer communication MC-10186068 and MC-10187382.
  • The bulletin applies to specified 2017–2018 Cadillac CT6 vehicles in North America and China equipped with 2.0L LTG, Automatic-Hybrid Electric (MRD), and RPO HP9.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Official NHTSA-hosted manufacturer communication: GM bulletin 19NA128: https://static.nhtsa.gov/odi/tsbs/2020/MC-10186068-9999.pdf

19. Frequently asked questions

What does P07A7 mean on an applicable Cadillac CT6?

GM bulletin 19NA128 identifies P07A7 as “Transmission Clutch 3 Stuck On” when set in the HPCM.

What symptoms are documented?

The bulletin documents an illuminated MIL and limited vehicle speed.

Which vehicles are covered by the supplied evidence?

Cadillac CT6 model years 2017–2018, with 2.0L LTG, Automatic-Hybrid Electric (MRD), and RPO HP9, in North America or China.

Is this a recall?

Not yet established by verified evidence.

20. Sources & verification

ReferenceVerified
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