P0B15
Issue in Hybrid/electric vehicle battery pack Voltage sensor B
Generic OBD-II
What it means
The hybrid control system reports a problem with voltage sensor B on the high-voltage battery pack. The sensor reads the voltage of one block of battery cells; its reading is missing, out of range or does not agree with the others. The stored name does not say the exact subtype.
Can I keep driving? Use caution: the hybrid system may cut power or shut down to protect the battery, so get it checked soon rather than driving on.
Common symptoms
What you'll notice
- Hybrid or check-engine warning light on
- Reduced power or limp mode
- Poor fuel economy
- Hybrid system may not start or may shut down
Common causes
Most likely first
- Loose, corroded or damaged sense wiring or connector at the battery
- Faulty voltage sensor or battery monitor
- Weak or unbalanced cell block, if the voltage is truly off
- Battery control module fault
How to diagnose & fix
Work through it in order
- Read all hybrid and battery codes and note which cell blocks are listed.
- Check the 12-volt battery and ground connections.
- Inspect the battery monitor connector and sense wiring, with the system off.
- Compare live cell-block voltages on the scanner; one block far from the others points to a real battery problem, while a missing or impossible reading points to wiring or the monitor.
- Do not open the battery pack or touch orange high-voltage cables; leave any high-voltage testing to a trained technician.
Related codes
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