P0BA4 code meaning
Hybrid/EV Battery Voltage Sense V Circuit
Powertrain system Generic code P0Bxx codes Check engine light
What P0BA4 means
P0BA4 reports an open or poorly connected sense V lead, the twenty-second channel and the last before W begins at P0BA9. GM's 2019 battery energy control module recognises it through seven cases, including 1.3 V between neighbouring cells, less than 36 mV with the balancing gate on and splice voltages above 0.1 or 0.5 V, with 0.8 s of failure in 1.6 s, Type A. The 2011 Volt already listed P0BA4 among its open sense line codes. In GM's 16OBDG02 programme a measured line resistance above 30.00 in 7 of 9 samples triggers it, in the eAssist mild hybrid low readings on lines N and N-1 together with a 0.5 V jump, Type B, gated by P1B38. Without a good sense lead the pack cannot balance or protect that cell.
P0BA4 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor1 to 10 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0BA4
- MIL and hybrid or EV system warning
- Vehicle may not become ready to drive
- Charging blocked
Common causes of P0BA4
- Most likelyBroken or unplugged sense lead V
- PossibleHigh-resistance splice or busbar joint on channel V
- Less likelyCell monitoring board fault on channel V
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 vWiring harnessBms
What each part of P0BA4 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. |
| A4 | The exact fault in that area. |
What to do next
- Note P0BA4 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 P0BA4
What does P0BA4 mean?
P0BA4 means "Hybrid/EV Battery Voltage Sense V Circuit". P0BA4 reports an open or poorly connected sense V lead, the twenty-second channel and the last before W begins at P0BA9. It is a generic code, so it means the same on every make.
Is it safe to drive with P0BA4?
Drive gently and only to a workshop. With P0BA4 the car can go into limp mode (reduced power) to protect itself.
Will P0BA4 fail an emissions test?
Yes, it can. P0BA4 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 P0BA4 to fix?
Difficulty: workshop only. A typical repair takes 1 to 10 hours of work. This is a job for a workshop.
Will P0BA4 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.