P2066 code meaning
Fuel Level Sensor B Performance
Powertrain system Generic code P20xx codes Check engine light
What P2066 means
P2066 flags a second fuel level sender whose reading is electrically valid but does not behave like real fuel. Makers test it differently. GM, on dual-tank trucks with an electric transfer pump, calls it Fuel Level Sensor 2 Performance and looks for a secondary reading that stays frozen while the engine burns 18 L or more, or that barely moves while the pump transfers fuel; Type B, two trips. Ford instead files a noisy signal here: more than 100 jumps of over 40 % between samples taken every 0.1 s, while a stuck sender B gets P25B1. Genesis compares calculated fuel use with the change the sender reports and revised that logic for the 2025 GV80 (25-01-026G). Jeep released PCM flashes for P2066 on 2021–2024 Grand Cherokee models, one symptom being a MIL after refuelling with the engine running. Mercedes uses P206600/P206609.
P2066 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.3 to 3 hours
- Clears after repairAfter a drive cycle
Symptoms of P2066
- Fuel gauge stays put or lags behind real consumption
- MIL after refuelling or long drives
- Range display and low fuel warning unreliable
Common causes of P2066
- Most likelyFloat arm sticking or sender card worn in one spot
- PossibleTransfer or jet pump not moving fuel between tank halves
- PossiblePlausibility logic needing a software update (Jeep, Genesis)
- Less likelyPoor contact causing a noisy signal (Ford definition)
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Fuel level sensor b
What each part of P2066 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 0 | Area: fuel and air metering and auxiliary emission controls. |
| 66 | The exact fault in that area. |
What to do next
- Note P2066 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 P2066
What does P2066 mean?
P2066 means "Fuel Level Sensor B Performance". P2066 flags a second fuel level sender whose reading is electrically valid but does not behave like real fuel. It is a generic code, so it means the same on every make.
Is it safe to drive with P2066?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P2066 fail an emissions test?
Yes, it can. P2066 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 P2066 to fix?
Difficulty: medium. A typical repair takes 0.3 to 3 hours of work. This is a job for a workshop.
Will P2066 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.