P0B61

What it means

P0B61 means the hybrid or EV control module has seen the signal from the high-voltage battery voltage sense 'H' circuit read higher than the expected range. The module compares this reading with other voltage measurements and with its expected limits. A signal that is too high, or implausible, sets the code. This can point to a wiring, connector or sensing fault rather than a real over-voltage, and which sensor is 'H' depends on the vehicle.

Symptoms

• Hybrid or EV system warning light on, often with the main malfunction light
• Reduced power or the car going into a limited performance mode
• Hybrid assist or EV driving unavailable, or the engine running more than usual
• Poor or reduced charging, or charging refused
• Poorly reported battery state of charge, or readings that jump about
• Car may not go into ready mode

Possible causes

• Faulty voltage sense circuit wiring, such as a short to voltage, a damaged harness or a chafed wirelikely
• Corroded, loose or contaminated connector at the battery pack, battery monitoring unit or control modulelikely
• Fault in the battery monitoring or voltage sensing electronics inside the battery packpossible
• Imbalanced or failing battery cells or modules causing a genuinely high or implausible readingpossible
• Fault in the hybrid or battery control modulerare
• Outdated control module software where the manufacturer has issued a known fix for this faultrare

How to diagnose

1. Read all stored and pending codes and note any other battery, isolation or communication codes, as they help to narrow down the cause
2. Review freeze frame data to see pack voltage, state of charge, temperature and vehicle state when the code set
3. Check for manufacturer service bulletins or software updates relevant to this model and code
4. Carry out a visual inspection of accessible harness and connectors for damage, water ingress, corrosion or heat marks, with the high-voltage system made safe first
5. Use live data to compare the 'H' sense voltage with total pack voltage and the other sense channels, and look for implausible readings
6. Check the individual cell or module voltages for imbalance, using the manufacturer's procedure
7. Test the sense circuit for continuity, short to voltage and resistance against the wiring diagram, once the high-voltage system is isolated by a trained technician
8. Clear the code and road test to see whether it returns, rechecking live data

How to fix

• Repair or replace the damaged wiring or terminals in the sense circuit
• Clean, reseat or replace corroded or loose connectors
• Repair or replace the faulty battery monitoring or sensing unit, following the model's procedure
• Rebalance or replace faulty battery modules or cells as the manufacturer specifies
• Replace or reprogram the control module only after the wiring and battery checks pass, or when a software update is the known fix

Can I keep driving?

Nearby codes

• P0B60GenericHybrid/EV Battery Voltage Sense H Circuit Low
• P0B62GenericHybrid/EV Battery Voltage Sense H Circuit Intermittent/Erratic