What it means
The control module monitors voltage in hybrid/EV battery A and sets this code when the measured voltage exceeds the expected range. The code identifies a high-voltage condition; it does not by itself establish whether the battery or its sensing circuit caused it.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Hybrid/EV battery A is a high-voltage battery section or assembly whose voltage is tracked by the battery control system. P0B26 sets when the reported voltage for battery A rises above the allowed range, which may indicate an actual high reading or an error in its sensing circuit.
Common causes
Most likely first.
- Battery A voltage above expected range
- Voltage measurement circuit fault
- Loose or poor electrical connection
Symptoms
- EV/hybrid system warning light on
- Reduced power output or limp mode
- Charging may fail or be slowed
- Reduced electric range
How to diagnose it
- Capture freeze-frame data and compare battery A's live voltage with other sections, especially during charging when the high reading appeared.
- Check for charging-system or battery codes that could point to an overcharge condition or another related fault.
- With the high-voltage system made safe according to the manufacturer's procedure, inspect battery A's connectors, terminals, and sensing wiring for corrosion, damage, or poor contact.
- Observe battery A voltage during charging and after charging stops to determine whether the high reading persists or appears intermittently.
- Test the battery A sensing circuit and section against the manufacturer's specifications to separate an inaccurate reading from a true high-voltage condition.
Common fixes
- Repair loose, corroded, or damaged connections at battery A.
- Repair damaged wiring or a fault in battery A's voltage-sensing circuit.
- Service the charging system or battery A section if testing confirms an actual excessive voltage.
Can I keep driving?
Avoid charging the vehicle or driving farther than necessary while this fault is active, since the system may limit power or charging to protect the battery. Stop safely and arrange service if a high-voltage warning appears, charging behaves abnormally, or power drops sharply.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.