P0B71 code meaning
Hybrid/EV Battery Voltage Sense K Circuit Intermittent/Erratic
Powertrain system Generic code P0Bxx codes Check engine light
What P0B71 means
P0B71 belongs to the unsteady fault type: the channel K reading flickers or drops out momentarily without staying beyond a fixed limit. No manufacturer documents this code publicly. Neither GM's hybrid tables from 2011 to 2019 nor the Ford and Chrysler bulletins on cell sense codes mention it, although they cover the open, plausibility, low and high codes of neighbouring channels. Its basis is the CARB requirement to monitor battery voltage sensors of the energy storage system as input components. In a workshop the approach would be a wiggle test on the module harness while watching cell voltage K live, plus a check of the connector terminals for fretting corrosion.
P0B71 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor1 to 8 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0B71
- Warning that comes and goes
- Occasional short loss of electric power
Common causes of P0B71
- Most likelyFretting corrosion on channel K connector terminals
- PossibleSense harness under strain losing contact with movement
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 kWiring harnessBms
What each part of P0B71 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. |
| 71 | The exact fault in that area. |
What to do next
- Note P0B71 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 P0B71
What does P0B71 mean?
P0B71 means "Hybrid/EV Battery Voltage Sense K Circuit Intermittent/Erratic". P0B71 belongs to the unsteady fault type: the channel K reading flickers or drops out momentarily without staying beyond a fixed limit. It is a generic code, so it means the same on every make.
Is it safe to drive with P0B71?
Drive gently and only to a workshop. With P0B71 the car can go into limp mode (reduced power) to protect itself.
Will P0B71 fail an emissions test?
Yes, it can. P0B71 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 P0B71 to fix?
Difficulty: workshop only. A typical repair takes 1 to 8 hours of work. This is a job for a workshop.
Will P0B71 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.