P0B70 code meaning
Hybrid/EV Battery Voltage Sense K Circuit High
Powertrain system Generic code P0Bxx codes Check engine light
What P0B70 means
P0B70 says that cell voltage K reads too high to be genuine. GM's 2019 battery energy control module sets it at 4.8 V or more, held for 1.4 s within 2 s, as a Type A fault with immediate MIL, and only when no communication loss, open sense line or internal module fault takes precedence. The same principle appears with other numbers elsewhere at GM: 4.65 V and 7 of 10 samples on the BAS Plus mild hybrid, 23 V for nickel-metal hydride block 11 on the 2012 two-mode trucks. The difference to P0B6F is the direction, not the location: a high reading typically comes from a lead touching a higher potential, a low one from a short to a lower one. Charging is usually blocked while it is active.
P0B70 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 P0B70
- Charging blocked
- MIL and power limitation
Common causes of P0B70
- Most likelyChannel K lead in contact with a higher tap
- PossibleFloating measuring input after loss of its lower reference
- Less likelyCell monitoring chip fault
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 P0B70 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. |
| 70 | The exact fault in that area. |
What to do next
- Note P0B70 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 P0B70
What does P0B70 mean?
P0B70 means "Hybrid/EV Battery Voltage Sense K Circuit High". P0B70 says that cell voltage K reads too high to be genuine. It is a generic code, so it means the same on every make.
Is it safe to drive with P0B70?
Drive gently and only to a workshop. With P0B70 the car can go into limp mode (reduced power) to protect itself.
Will P0B70 fail an emissions test?
Yes, it can. P0B70 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 P0B70 to fix?
Difficulty: workshop only. A typical repair takes 1 to 8 hours of work. This is a job for a workshop.
Will P0B70 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.