In some cases, a TSB (Technical Service Bulletin) requires an ECU update to fix the power management software. Conclusion

: The sensor tracks how much current is going into or out of the battery. The Engine Control Module (ECM) uses this data to manage the alternator's output and optimize fuel efficiency through the smart charging system. Illuminated Check Engine Light (MIL). Charging system warnings.

Fixing a P155B-00 code requires a blend of physical inspection and digital diagnosis. Follow these steps to resolve the issue: Step 1: Scan and Record Live Data

: The Energy Management system continuously reads battery state-of-charge (SoC), internal battery temperature, and current voltage to determine if the engine can safely shut off at red lights without draining auxiliary electronics.

The ECM uses this data to regulate the charging voltage (variable voltage charging system) to improve fuel economy and extend battery life.

Code P155B-00 sets when the ECM detects that the signal from the Battery Current Sensor is out of the expected range, inconsistent, or does not correlate with other data (like battery temperature or voltage). Essentially, the computer cannot accurately read how much electricity the car is using or charging.

Nissan P155b-00 !!exclusive!! Jun 2026

In some cases, a TSB (Technical Service Bulletin) requires an ECU update to fix the power management software. Conclusion

: The sensor tracks how much current is going into or out of the battery. The Engine Control Module (ECM) uses this data to manage the alternator's output and optimize fuel efficiency through the smart charging system. Illuminated Check Engine Light (MIL). Charging system warnings.

Fixing a P155B-00 code requires a blend of physical inspection and digital diagnosis. Follow these steps to resolve the issue: Step 1: Scan and Record Live Data

: The Energy Management system continuously reads battery state-of-charge (SoC), internal battery temperature, and current voltage to determine if the engine can safely shut off at red lights without draining auxiliary electronics.

The ECM uses this data to regulate the charging voltage (variable voltage charging system) to improve fuel economy and extend battery life.

Code P155B-00 sets when the ECM detects that the signal from the Battery Current Sensor is out of the expected range, inconsistent, or does not correlate with other data (like battery temperature or voltage). Essentially, the computer cannot accurately read how much electricity the car is using or charging.