P0B8B

Hybrid/EV Battery Voltage Sense Q Circuit

Severity

🔴 High

Can you drive?

Limited driving only, diagnose soon

Approx. repair cost

$56–167 (est.)

Symptoms

Check Engine light comes on
Hybrid system power reduction
The vehicle goes into emergency mode
Reduced driving range (for electric vehicles)
Battery error message on dashboard

Causes

Open or short circuit in the Q section sensor circuit
Battery Monitoring Module (BMS) malfunction
Corrosion or poor contact in the measuring circuit connectors
Problems with the high-voltage battery (unbalanced sections)
Damage to the wiring harness near the battery

How to Fix

Check the integrity of the wires and connectors of the section Q sensor circuit
Check the resistance and signal of the voltage sensor
Scan the BMS module for additional errors
Check the voltage balance of all battery sections
If necessary, replace the sensor or repair the wiring

Related codes

P0B8A P0B8C P0B89