P0B73 code meaning
Hybrid/EV Battery Voltage Sense L Circuit Range/Performance
Powertrain system Generic code P0Bxx codes Check engine light
What P0B73 means
Channel L delivers a value, but P0B73 tells you that the value is not credible. GM checks this in three ways. The 2016 Chevrolet Volt and the 2019 lithium-ion systems test whether cell L moves in the same direction as the average once that average changes by more than 0.022 V, failing 7 of 8 seconds or 35 of 40 samples respectively, Type A. The BAS Plus mild hybrid demands at least half of the average movement, 20 of 40 samples, Type B. The 2012 two-mode trucks treat L as nickel-metal hydride block 12 and compare blocks 12 and 13, scaled by twenty, with the pack voltage, failing beyond 70 V in 160 of 170 samples, Type B. A battery controller reflash or measuring board repair is the usual remedy.
P0B73 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor0.3 to 8 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0B73
- MIL with normal driving behaviour
- Reduced electric range or assist
Common causes of P0B73
- Most likelyChannel L input not following real cell voltage changes
- PossibleBattery controller software or calibration issue
- Less likelyCorroded cell tap slowing the signal
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hv battery voltage sense lWiring harnessBms
What each part of P0B73 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| B | Area: hybrid propulsion. |
| 73 | The exact fault in that area. |
What to do next
- Note P0B73 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0B73
What does P0B73 mean?
P0B73 means "Hybrid/EV Battery Voltage Sense L Circuit Range/Performance". Channel L delivers a value, but P0B73 tells you that the value is not credible. It is a generic code, so it means the same on every make.
Is it safe to drive with P0B73?
Drive gently and only to a workshop. With P0B73 the car can go into limp mode (reduced power) to protect itself.
Will P0B73 fail an emissions test?
Yes, it can. P0B73 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0B73 to fix?
Difficulty: workshop only. A typical repair takes 0.3 to 8 hours of work. This is a job for a workshop.
Will P0B73 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.