P0B93: Hybrid/EV Battery Voltage Sense R Circuit High

A reading on sense R above anything a healthy cell could produce sets P0B93. GM's lithium-ion battery controllers of 2016 and 2019 use 4.8 V or more, held 1.4 s within 2 s, as a Type A fault. The 16OBDG02 programme with its own battery sensor module draws the line at 4.90 V, 14 of 18 samples. GM's eAssist mild hybrid already reacts above 4.65 V (7 of 10 samples, Type B). On the 2012 two-mode trucks the channel is nickel-metal hydride block 18, which must exceed 23 V in 15 of 20 samples, Type B. Because a cell this high would be dangerous, an electrical fault is far more likely: a sense lead touching a higher potential, or a damaged measuring input on the monitoring board.

Symptoms

• MIL and hybrid system warning
• Charging or regeneration cut back
• Reduced power mode

Most likely causes

• Sense lead R in contact with a higher cell potential
• Damaged measuring input for channel R
• Cell on channel R actually overcharged

What to check, in order

Start with the simplest. You can tick off each step.

1. Read the codes with a hybrid-compatible scanner and write down the freeze frame data
2. Check the sensor's ground and make sure the signal wire is not receiving voltage from another circuit.
3. Make sure the battery cooling air intake is clean
4. Check the 12 V auxiliary battery, which can also trigger warnings
5. Leave any high-voltage measurements to a specialized repair shop

Good to know

• It can trigger limp mode.
• It affects emissions.

What each character of P0B93 means

• P: Powertrain: engine and transmission
• 0: Generic code: same on every make
• B: Subsystem depends on the code range
• 93: Specific fault in that system

Frequently asked questions

Can I keep driving with code P0B93?

If the car still runs, drive as little as possible and go to a specialized repair shop. Do not touch the orange cables: they carry high voltage.

What causes code P0B93?

The most common causes are: sense lead R in contact with a higher cell potential; damaged measuring input for channel R; cell on channel R actually overcharged.

Related codes

• P0B90Hybrid/EV Battery Voltage Sense R Circuit
• P0B91Hybrid/EV Battery Voltage Sense R Circuit Range/Performance
• P0B92Hybrid/EV Battery Voltage Sense R Circuit Low
• P0B94Hybrid/EV Battery Voltage Sense R Circuit Intermittent/Erratic
• P0B8EHybrid/EV Battery Voltage Sense Q Circuit High
• P0B98Hybrid/EV Battery Voltage Sense S Circuit High

Sources

• gsi.ext.gm.com: 19OBDG01 Hybrid Diagnostics
• gsi.ext.gm.com: 16OBDG02 Hybrid Diagnostics
• gsi.ext.gm.com: 13OBDG05C Hybrid Diagnostics
• gsi.ext.gm.com: 12OBDG06 Hybrid Diagnostics

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.