Nissan P155b00 ((hot)) May 2026

Seeing a new code can induce panic, but knowledge is power. In this deep-dive article, we will explain exactly what the P155B00 code means, why it appears, the most common symptoms you’ll notice, how to diagnose it correctly, and the steps to fix it—without replacing the entire hybrid battery if possible. P155B00 is a manufacturer-specific Diagnostic Trouble Code (DTC) for Nissan hybrid vehicles. It translates to: "Hybrid Battery Pack Internal Resistance Abnormal (Module Imbalance)."

Ignoring P155B00 can damage the entire hybrid battery pack. The healthy modules will be forced to overcompensate for the weak one, leading to a cascading failure. Continued driving also risks overheating the battery, which could trigger a failure of the high-voltage safety contactors (requiring a full pack replacement). nissan p155b00

A: The system is monitoring the issue but hasn’t confirmed it yet. Drive gently for a few days. If it doesn’t go away, perform a calibration or cleaning now. It’s easier to fix pre-failure. Final Verdict The Nissan P155B00 code is not a death sentence for your hybrid. In many cases, a simple cleaning of bus bars, a cooling filter change, and a BMS reset will clear the code for years. However, if ignored, it will escalate into a complete battery failure. Seeing a new code can induce panic, but knowledge is power

In plain English, your Nissan’s onboard computer (the Hybrid Vehicle Control ECU or HVCM) has detected that the internal electrical resistance within one or more of the battery modules has deviated too far from the expected range compared to the other modules. Lithium-ion (or NiMH) battery modules naturally have a small amount of internal resistance. Over time, connections can loosen, cells can degrade, or temperature differences can cause one module to behave differently. When one module’s resistance is significantly higher (or lower) than its neighbors, the battery pack can no longer charge or discharge evenly. This creates a "weak link" that reduces overall performance and can lead to overheating. It translates to: "Hybrid Battery Pack Internal Resistance