P0B49 code meaning
Hybrid/EV Battery Voltage Sense C Circuit Intermittent/Erratic
Powertrain system Generic code P0Bxx codes Check engine light
What P0B49 means
P0B49 is reserved for a channel C signal that jumps or drops out briefly instead of failing for good. No manufacturer documents this code publicly; GM, which uses the other four channel C codes, has no erratic test for it in its published tables. A technician would start from the freeze frame and log cell voltage C next to its neighbours while flexing the module harness, because a loose crimp or a cracked solder joint on the monitoring board shows up as spikes that a permanent test misses. CARB requires battery voltage sensors of the energy storage system to be monitored like any input and faults to be tied to the smallest replaceable unit. Warnings may come and go.
P0B49 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 P0B49
- Warning light that appears and disappears
- Occasional short loss of electric drive power
Common causes of P0B49
- Most likelyLoose crimp or connector on the channel C sense line
- PossibleCracked solder joint on the cell monitoring board
- Less likelyElectrical noise from the inverter coupling into the sense line
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 cWiring harnessBms
What each part of P0B49 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. |
| 49 | The exact fault in that area. |
What to do next
- Note P0B49 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 P0B49
What does P0B49 mean?
P0B49 means "Hybrid/EV Battery Voltage Sense C Circuit Intermittent/Erratic". P0B49 is reserved for a channel C signal that jumps or drops out briefly instead of failing for good. It is a generic code, so it means the same on every make.
Is it safe to drive with P0B49?
Drive gently and only to a workshop. With P0B49 the car can go into limp mode (reduced power) to protect itself.
Will P0B49 fail an emissions test?
Yes, it can. P0B49 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 P0B49 to fix?
Difficulty: workshop only. A typical repair takes 0.5 to 8 hours of work. This is a job for a workshop.
Will P0B49 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.