P0B59 code meaning
Hybrid/EV Battery Voltage Sense G Circuit
Powertrain system Generic code P0Bxx codes Check engine light
What P0B59 means
Voltage sense G is the seventh cell measuring channel; how many cells or groups it covers depends on how the manufacturer splits the pack among monitoring chips. P0B59 is its open-circuit code. Two Ford bulletins name it: the 2019-2020 Fusion PHEV, where the open-line group up to P0B7C leads to a battery replacement, and the 2023 Mach-E and E-Transit, where it is blamed on the BECM flexible printed circuit. GM's BECM sets it after 0.6 s of an open-line pattern such as adjacent cells 1.3 V apart, a balanced cell under 36 mV or splice voltages above 0.1 V or 0.5 V, Type A. If several channels report at once, suspect a shared connection first.
P0B59 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor0.5 to 8 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0B59
- Vehicle not ready to drive
- Charging blocked
- Wrench light or hybrid warning
Common causes of P0B59
- Most likelyOpen channel G tap, splice or bus bar contact
- PossibleIntermittent BECM flexible circuit (Ford Mach-E, E-Transit)
- Less likelyInternal traction battery failure (Ford Fusion PHEV)
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hv battery voltage sense gWiring harnessBms
What each part of P0B59 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| B | Area: hybrid propulsion. |
| 59 | The exact fault in that area. |
What to do next
- Note P0B59 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0B59
What does P0B59 mean?
P0B59 means "Hybrid/EV Battery Voltage Sense G Circuit". Voltage sense G is the seventh cell measuring channel; how many cells or groups it covers depends on how the manufacturer splits the pack among monitoring chips. It is a generic code, so it means the same on every make.
Is it safe to drive with P0B59?
Drive gently and only to a workshop. With P0B59 the car can go into limp mode (reduced power) to protect itself.
Will P0B59 fail an emissions test?
Yes, it can. P0B59 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0B59 to fix?
Difficulty: workshop only. A typical repair takes 0.5 to 8 hours of work. This is a job for a workshop.
Will P0B59 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.