Cause
Faulty battery pack sensor module
The sensing board inside the traction battery — the electronics that read every cell group's voltage and every temperature sensor, and feed the battery management its raw data. When it fails, every measurement it made becomes suspect at once: impossible voltages, disagreeing temperatures, a burst of simultaneous battery codes that reads like a catastrophic pack failure and is not.
That burst is the tell. Forty cell groups do not fail together in an instant; one shared sensing board does — the corpus's one-shared-thing argument, inside the pack. The distinction is worth thousands, because the board is a fraction of a pack's price even though replacing it is pack-opening work. A battery condemned on a sudden cluster of wild readings deserves this diagnosis considered first.
Typically specialist work. Needs equipment or training most home workshops do not have.
Some of these codes mean you should stop driving
3 of the 305 codes this can cause indicate a fault where continuing to drive risks damage or is unsafe. Which one you have matters more than the cause does — read the code's own page before deciding.
Codes this can cause (305)
Codes where this is a likely explanation first, rather than merely a possible one.
- P0AFB Hybrid/EV Battery System Voltage High Likely for this code High
- P0AFC Hybrid/EV Battery Pack Sensor Module Likely for this code High
- P0D34 Hybrid/EV Battery System Current Likely for this code High
- P0D36 Hybrid/EV Battery System Current Low Likely for this code Moderate
- P0D37 Hybrid/EV Battery System Current High Likely for this code High
- P0D85 Battery Charging Output Voltage Too High Likely for this code Critical
- P0DAB Hybrid/EV Battery Cell Balancing Performance Likely for this code High
- P0DAC Hybrid/EV Battery Cell Balancing Circuit A Likely for this code High
- P0DAD Hybrid/EV Battery Cell Balancing Circuit A Stuck On Likely for this code High
- P0DAE Hybrid/EV Battery Cell Balancing Circuit A Stuck Off Likely for this code Moderate
- P0DAF Hybrid/EV Battery Cell Balancing Circuit A Range/Performance Likely for this code Moderate
- P0DB0 Hybrid/EV Battery Cell Balancing Circuit B Likely for this code High
- P0DB1 Hybrid/EV Battery Cell Balancing Circuit B Stuck On Likely for this code High
- P0DB2 Hybrid/EV Battery Cell Balancing Circuit B Stuck Off Likely for this code Moderate
- P0DB3 Hybrid/EV Battery Cell Balancing Circuit B Range/Performance Likely for this code Moderate
- P0DB4 Hybrid/EV Battery Cell Balancing Circuit C Likely for this code High
- P0DB5 Hybrid/EV Battery Cell Balancing Circuit C Stuck On Likely for this code High
- P0DB6 Hybrid/EV Battery Cell Balancing Circuit C Stuck Off Likely for this code Moderate
- P0DB7 Hybrid/EV Battery Cell Balancing Circuit C Range/Performance Likely for this code Moderate
- P0DB8 Hybrid/EV Battery Cell Balancing Circuit D Likely for this code High
- P0DB9 Hybrid/EV Battery Cell Balancing Circuit D Stuck On Likely for this code High
- P0DBA Hybrid/EV Battery Cell Balancing Circuit D Stuck Off Likely for this code Moderate
- P0DBB Hybrid/EV Battery Cell Balancing Circuit D Range/Performance Likely for this code Moderate
- P0DBC Hybrid/EV Battery Cell Balancing Circuit E Likely for this code High
- P0DBD Hybrid/EV Battery Cell Balancing Circuit E Stuck On Likely for this code High
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Others who found this
Be the first to write this up
Nothing posted about this yet. Whatever you found is worth writing down — even a dead end saves someone the same afternoon.
What makes one worth reading:
- The car — make, model, year and engine. The same fault behaves differently on each.
- What you measured, not only what you replaced.
- What actually fixed it — or that nothing did, which is worth knowing too.
Sign in or create an account to add what you found about Faulty battery pack sensor module.