P0B67

Code

Generic P — Powertrain

Hybrid/EV Battery Voltage Sense I Circuit Intermittent/Erratic

Brand: Generic

Type: P — Powertrain

Views: UK: 28 EN: 41 RU: 18

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Read freeze-frame and freeze data; note when and under what conditions the fault set
Scan for related DTCs (other battery sense circuits, BMS communication codes)
Visually inspect harness routing, clips and protective sleeving for chafe or damage
Inspect battery module connectors and pins for corrosion, bent pins, or moisture
Check and clean mating surfaces; ensure secondary locks/seals are engaged
Measure voltage at the BMS sense input and at the module tap using a DMM and oscilloscope

Sense circuit provides a DC voltage proportional to module/pack voltage (typically scaled to BMS input range, e.g., 0–5.0 V)
Expected steady reading corresponds to measured module tap voltage within manufacturer tolerance (commonly ±0.1–0.5 V after scaling)
Noise/variation should be minimal; transient spikes or rapid jumps are abnormal
No open-circuit (infinite resistance) or direct short to chassis/positive should be present
Intermittent signals may appear as brief dropouts, rapid voltage swings, or random spikes on a scope trace

Record current DTCs and freeze-frame data. Note driving/charging conditions when fault occurred.
Clear codes and attempt to reproduce P0B67 while monitoring live voltage-sense channel(s) with a scanner.
Visually inspect all battery pack sense harnesses, connectors, and grounds for damage, corrosion or looseness.
With HV system made safe per manufacturer procedures, perform continuity and resistance checks of the sense wiring from the BMS connector to the battery tap(s).
Backprobe BMS sense input and corresponding module tap with a DMM (DC volts) to compare actual module voltage vs. scaled sense voltage; record differences.
Use an oscilloscope at the BMS input to look for intermittent dropouts, spikes, or high-frequency noise while performing wiggle tests on harness and connectors.
If intermittent behavior is reproduced, isolate the affected segment (connector, pigtail, module) and perform connector cleaning/repair or replace damaged wiring.
If wiring and connectors check good, test or replace the affected module sense PCB or the BMS input module per manufacturer guidance.
After repairs, clear codes and perform a full system check: charge/discharge cycles and road/drive test to confirm the code does not return.
If problem persists, consult manufacturer technical service bulletins and consider BMS reflash, module replacement, or professional BMS-level diagnostics.

Damaged/chafed sense harness at a sharp edge or moving component causing intermittent contact
Corroded or loose pack/module connector pin(s) producing intermittent conductivity
Failing module voltage-sense PCB or resistor divider on a battery module
Poor/high-resistance battery pack ground connection
Intermittent connector mating due to contaminated secondary locking or seal
BMS input circuit degraded or intermittent internal component failure