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Chevrolet P0A40

match that engineering is aware of at this time. If the code comes back or the data does not match then contact GM TAC (1-800-446-8227) for further repair direction. Warranty Infor

DriveNot yet established by verified evidence. The bulletin includes a 10-mile test drive as part of a technician validation process, but this does not establish general driving safety for every vehicle with P0A40.
ChargeNot yet established by verified evidence.
ServiceContact a Chevrolet/GM-qualified service facility. Per PIC3604, technicians should contact GM TAC at 1-800-446-8227 if the bulletin data does not match or P0A40 returns.
Confidence95%

Quick answer

For a 2017 Chevrolet Bolt EV in the U.S., GM bulletin PIC3604 documents a P0A40 condition that may be related to a known calibration mismatch when the bulletin’s specified data matches and the code does not return after its validation procedure. If the code returns or the data does not match, GM directs technicians to contact GM TAC for further repair direction.

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 P0A40 mean?

For a 2017 Chevrolet Bolt EV in the U.S., GM bulletin PIC3604 documents a P0A40 condition that may be related to a known calibration mismatch when the bulletin’s specified data matches and the code does not return after its validation procedure. If the code returns or the data does not match, GM directs technicians to contact GM TAC for further repair direction.

2. Technical explanation

The verified evidence is a GM manufacturer communication filed with NHTSA: PIC3604, published September 7, 2017. Its available text references checking a Hybrid Powertrain Control Module value of less than 10 V, clearing DTCs, performing five key cycles with the driver door opened and closed between cycles, checking whether P0A40 resets, and test-driving for 10 miles to confirm that it does not reset. When the specified data matches and the code does not return, the bulletin says the vehicle may be released because of a calibration mismatch known to engineering. If the data does not match or P0A40 returns, the bulletin directs contact with GM Technical Assistance Center (TAC) for further repair direction.

3. What system is affected?

Not yet established by verified evidence. The bulletin text references the Hybrid Powertrain Control Module.

4. How serious is this code?

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

5. Symptoms you may notice

  • A stored or returning P0A40 diagnostic trouble code is established by the supplied evidence.
  • Other driver-observable symptoms are not yet established by verified evidence.

6. Possible causes

  • A calibration mismatch known to engineering is documented as a possible explanation only when the bulletin’s specified data matches and P0A40 does not return after the prescribed validation.
  • Any other cause is not yet established by verified evidence.

7. Can I still drive the vehicle?

Not yet established by verified evidence. The bulletin includes a 10-mile test drive as part of a technician validation process, but this does not establish general driving safety for every vehicle with P0A40.

8. Can I charge the vehicle?

Not yet established by verified evidence.

9. What you can safely do

  • Arrange diagnosis by a Chevrolet/GM-qualified service facility.
  • Provide the technician with NHTSA manufacturer communication PIC3604 / MC-10156996.
  • Do not attempt high-voltage system diagnosis or repair yourself.
  • If P0A40 returns after evaluation, follow GM service direction; the bulletin directs technicians to contact GM TAC when the data does not match or the code returns.

10. Step-by-step troubleshooting

  1. Verified technician procedure in PIC3604: check the bulletin-specified Hybrid Powertrain Control Module data condition referenced in the communication.
  2. If the applicable data matches, clear DTCs.
  3. Perform five key cycles, including opening and closing the driver door between key cycles.
  4. Check whether P0A40 has reset.
  5. Test-drive for 10 miles and verify whether P0A40 resets.
  6. If the data matches and P0A40 does not return, the bulletin states the vehicle may be released due to the documented calibration mismatch.
  7. If the data does not match or P0A40 returns, the bulletin directs technicians to contact GM TAC at 1-800-446-8227 for further repair direction.

11. When to contact service

Contact a Chevrolet/GM-qualified service facility. Per PIC3604, technicians should contact GM TAC at 1-800-446-8227 if the bulletin data does not match or P0A40 returns.

12. What the service center may check

  • Review applicability of GM bulletin PIC3604 for the vehicle.
  • Evaluate the bulletin-specified Hybrid Powertrain Control Module data condition.
  • Clear DTCs and perform the documented key-cycle validation.
  • Confirm whether P0A40 returns after the documented 10-mile test drive.
  • Contact GM TAC if the code returns or data does not match.

13. Possible repair or resolution

  • When the bulletin’s data matches and P0A40 does not return after the documented validation, PIC3604 identifies a known calibration mismatch and states that the vehicle may be released.
  • When P0A40 returns or the data does not match, further resolution is not specified in the supplied evidence; GM TAC direction is required.

14. Affected vehicles

15. Related TSBs / service bulletins

  • GM PIC3604, filed with NHTSA as MC-10156996, published September 7, 2017. Verified applicability: 2017 Chevrolet Bolt EV, U.S. The communication addresses P0A40 validation and a possible known calibration mismatch under specified conditions.

16. Recall information

  • No recall is established by the supplied verified evidence.

17. Official manufacturer information

NHTSA Manufacturer Communication PDF 10156996: PIC3604, September 7, 2017: https://static.nhtsa.gov/odi/tsbs/2017/MC-10156996-9999.pdf

19. Frequently asked questions

What does P0A40 mean on a 2017 Chevrolet Bolt EV?

The supplied diagnostic record does not provide a verified plain-language definition. PIC3604 documents a P0A40 condition and a possible calibration mismatch when the bulletin’s specified data matches and the code does not return after validation.

Does P0A40 require repair?

Not always, based on PIC3604. If the specified data matches and P0A40 does not return after the bulletin procedure, GM states the vehicle may be released because of a known calibration mismatch. If it returns or the data does not match, GM directs technician contact with TAC for further repair direction.

Can I drive with P0A40?

Not yet established by verified evidence. A service facility should assess the vehicle.

Is there a Chevrolet service bulletin for P0A40?

Yes. PIC3604 / NHTSA MC-10156996 is verified for the 2017 Chevrolet Bolt EV in the U.S.

20. Sources & verification

ReferenceVerified
Chevrolet P0A40: match that engineering is aware of at this time. If… | EV Diagnostics