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Chevrolet P1FFF

System Isolation / Coolant Level Sensor Fault - Hybrid/EV Battery Charging System Disabled Cause This condition may be caused by a set code in the Hybrid Powertrain Control Module

DriveNot yet established by verified evidence.
ChargeThe verified P1FFF description states that the Hybrid/EV battery charging system is disabled. Whether charging is always unavailable in every occurrence is not yet established by verified evidence.
ServiceService support is appropriate because the verified bulletin associates P1FFF with the charging system being disabled and a possible Battery Energy Control Module hardware fault.
Confidence95%

Quick answer

For a 2017 Chevrolet Bolt EV (US), DTC P1FFF is documented in GM bulletin 17NA328 as: “System Isolation / Coolant Level Sensor Fault - Hybrid/EV Battery Charging System Disabled.” The bulletin states it may be caused by a code set in Hybrid Powertrain Control Module 2 (HPCM2) together with a hardware fault in the Battery Energy Control Module.

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 P1FFF mean?

For a 2017 Chevrolet Bolt EV (US), DTC P1FFF is documented in GM bulletin 17NA328 as: “System Isolation / Coolant Level Sensor Fault - Hybrid/EV Battery Charging System Disabled.” The bulletin states it may be caused by a code set in Hybrid Powertrain Control Module 2 (HPCM2) together with a hardware fault in the Battery Energy Control Module.

2. Technical explanation

Verified evidence identifies P1FFF as a charging-system-disable diagnostic associated with system isolation/coolant-level-sensor fault wording. GM bulletin 17NA328 links this condition to an HPCM2-set code in conjunction with a Battery Energy Control Module hardware fault. The supplied evidence does not establish a complete diagnostic path, component-level failure mechanism, or owner-performed repair procedure.

3. What system is affected?

Hybrid/EV battery charging system; Battery Energy Control Module; Hybrid Powertrain Control Module 2 (HPCM2).

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

  • Hybrid/EV battery charging system disabled is included in the verified P1FFF diagnostic description.

6. Possible causes

  • A code set in HPCM2 in conjunction with a hardware fault in the Battery Energy Control Module, according to GM bulletin 17NA328.

7. Can I still drive the vehicle?

Not yet established by verified evidence.

8. Can I charge the vehicle?

The verified P1FFF description states that the Hybrid/EV battery charging system is disabled. Whether charging is always unavailable in every occurrence is not yet established by verified evidence.

9. What you can safely do

  • Arrange professional diagnosis by a Chevrolet/GM-qualified EV service facility.
  • Do not attempt high-voltage battery, Battery Energy Control Module, or HPCM2 repairs yourself based on this information.

10. Step-by-step troubleshooting

  1. A service facility can evaluate P1FFF in the context of any accompanying HPCM2 and battery-control-module diagnostic codes.
  2. GM bulletin 17NA328 should be reviewed during diagnosis for applicable 2017 Chevrolet Bolt EV vehicles.

11. When to contact service

Service support is appropriate because the verified bulletin associates P1FFF with the charging system being disabled and a possible Battery Energy Control Module hardware fault.

12. What the service center may check

  • Retrieve all stored diagnostic trouble codes, including codes set by HPCM2.
  • Evaluate the Battery Energy Control Module for the hardware-fault condition described in GM bulletin 17NA328.
  • Review GM bulletin 17NA328 and follow its applicable diagnostic and correction information.

13. Possible repair or resolution

  • Not yet established by verified evidence. The supplied bulletin excerpt identifies a Battery Energy Control Module hardware fault as part of the condition but does not provide the complete verified repair outcome.

14. Affected vehicles

15. Related TSBs / service bulletins

  • GM/NHTSA manufacturer communication 17NA328, NHTSA document MC-10137377-9999, published February 22, 2018. It applies in the supplied evidence to the 2017 Chevrolet Bolt EV in the US and includes P1FFF among the listed DTCs.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Official source: NHTSA manufacturer communication PDF 10137377 / GM bulletin 17NA328: https://static.nhtsa.gov/odi/tsbs/2018/MC-10137377-9999.pdf

19. Frequently asked questions

What does P1FFF mean on a 2017 Chevrolet Bolt EV?

The verified description is: “System Isolation / Coolant Level Sensor Fault - Hybrid/EV Battery Charging System Disabled.”

What does GM bulletin 17NA328 identify as a possible cause?

It states that the condition may be caused by a code set in HPCM2 in conjunction with a hardware fault in the Battery Energy Control Module.

Can I drive with P1FFF?

Not yet established by verified evidence.

Can I charge with P1FFF?

The diagnostic description says the Hybrid/EV battery charging system is disabled; the supplied evidence does not establish charging behavior in every case.

20. Sources & verification

Verified
Chevrolet P1FFF: System Isolation / Coolant Level Sensor Fault -… | EV Diagnostics