P0B49Hybrid/EV Battery Voltage Sense C Circuit Intermittent/Erratic
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- 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.
- What you may notice
- Warning light that appears and disappears
- Occasional short loss of electric drive power
- Likely causes
- LikelyLoose crimp or connector on the channel C sense line
- PossibleCracked solder joint on the cell monitoring board
- RareElectrical noise from the inverter coupling into the sense line
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €80 – €6,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.